Jerry and Katie not only don't know what they are talking about, they are slanderers who would destroy the teachings.

"So, you think there is potential for Myoho Renge Kyo to be diminished by any human, karmic impediment ?If that were true, then the Buddha lied when He proclaimed achieving His purpose for advent in this threefold world. I don’t buy it — Doom sayers have existed since the dawn of human life on this planet—but Shakyamuni’s enlightenment secured the end to that nonsense — Maybe you just don’t believe the Lotus Sutra- yet? Keep chanting Myoho Renge Kyo- nothing else is required😊 - Katie and or Jerry

Not only diminished but destroyed. It is slanderers like you and especially SGI/NST who are the worms in the body of the lion who will destroy the Law.

Nichiren teaches:

“If even a good monk sees someone destroying the teaching and disregards him, failing to reproach him, to oust him, or to punish him for his offense, then you should realize that that monk is betraying the Buddha’s teaching. But if he ousts the destroyer of the Law, reproaches him, or punishes him, then he is my disciple and a true voice-hearer.”

This admonition urged me on, and I spoke out against slander in spite of the various persecutions I faced, because I would have become an enemy of the Buddha’s teaching if I had not.

Slander can be either minor or serious, however, and sometimes we should overlook it rather than attack it. The True Word and Tendai schools slander the Lotus Sutra and should be severely rebuked. But without great wisdom it is hard to differentiate correctly between their doctrines and the teachings that Nichiren spreads. Therefore, at times we refrain from attacking them, just as I did in On Establishing the Correct Teaching for the Peace of the Land.2

Whether or not we speak out, it will be difficult for those who have committed the grave offense of slander to avoid retribution. Our seeing, hearing, and making no attempt to stop slander that, if we spoke out, could be avoided, destroys our gifts of sight and hearing, and is utterly merciless.

Chang-an writes, “If one befriends another person but lacks the mercy to correct him, one is in fact his enemy.”3 The consequences of a grave offense are extremely difficult to erase. The most important thing is to continually strengthen our wish to benefit others.

When a person’s offense is minor, admonishment is sometimes called for, but at other times it may be unnecessary, for there are those who may correct themselves without being told. Reprove a person for slander when necessary, so that you can forestall for both of you the consequences of an offense. Then, you should forgive that person. The point is that even minor slanders may lead to serious ones, and then the effects one must suffer would be far worse. This is [what Chang-an means when he writes], “One who rids the offender of evil is acting as his parent.”4

Many such examples of slander are also found among Nichiren’s disciples and lay believers....*" - The Embankments of Faith

Like Ichinosawa and the SGI members who mix the teachings of the Lotus Sutra with the Shingon teaching of Yuiga Yoga, SGI and Nichiren Shu who practice interfaith, and those who are complicit with their slanders, like Jerry and Katie

Nichiren further explains the above passage of the Nirvana Sutra in the Opening of the Eyes:

"Answer: The Nirvana Sutra says: “If even a good monk sees someone destroying the teaching and disregards him, failing to reproach him, to oust him, or to punish him for his offense, then you should realize that that monk is betraying the Buddha’s teaching. But if he ousts the destroyer of the Law, reproaches him, or punishes him, then he is my disciple and a true voice-hearer.”

Chang-an comments on this as follows: “One who destroys or brings confusion to the Buddha’s teachings is betraying them. If one befriends another person but lacks the mercy to correct him, one is in fact his enemy. But one who reprimands and corrects an offender is a voice-hearer who defends the Buddha’s teachings, a true disciple of the Buddha. One who rids the offender of evil is acting as his parent. Those who reproach offenders are disciples of the Buddha. But those who do not oust offenders are betraying the Buddha’s teachings." - Opening of the Eyes

"The sutra states, “Those persons who had heard the Law dwelled here and there in various Buddha lands, constantly reborn in company with their teachers,”6 and “If one stays close to the teachers of the Law, one will speedily gain the bodhisattva way. By following and learning from these teachers one will see Buddhas as numerous as Ganges sands.”7 A commentary says, “Originally one followed this Buddha and for the first time conceived the desire to seek the way. And by following this Buddha again, one will reach the stage where there is no retrogression.” Another commentary says, “In the beginning one followed this Buddha or bodhisattva and formed a bond with him, and so it will be through this Buddha or bodhisattva that one will attain one’s goal.”9 Above all, be sure to follow your original teacher so that you are able to attain Buddhahood. Shakyamuni Buddha is the original teacher for all people, and moreover, he is endowed with the virtues of sovereign and parent. Because I have expounded this teaching, I have been exiled and almost killed. As the saying goes, “Good advice grates on the ear.” But still I am not discouraged. The Lotus Sutra is like the seed, the Buddha like the sower, and the people like the field. If you deviate from these principles, not even I can save you in your next life." - The Essential for Attaining Buddhahood

Those who follow different teachers than the Original Eternal Buddha Shakyamuni and his foremost disciple Nichiren and  especially those who exhort others to follow another teacher are also worms in the body of the lion Law who destroy the Law of Namu Myoho renge kyo.

"...The impurity of thought has been such that, as the Former and Middle Days of the Law gradually passed, people transmitted insignificant erroneous teachings while destroying the unfathomable correct teaching. It therefore appears that more people have fallen into the evil paths because of errors with respect to Buddhism than because of secular misdeeds." - Encouragement to a Sick Person.

"The Great Collection Sutra states, “The sun and moon no longer shed their light. All the four directions will be afflicted by drought.... The wicked rulers and monks who perform these ten evil acts will curse and destroy my correct teaching.” In the Benevolent Kings Sutra we read, “Evil monks, hoping to gain fame and profit, in many cases appear before the ruler, the crown prince, or the other princes, and take it upon themselves to preach doctrines that lead to the violation of the Buddhist Law and the destruction of the nation. The ruler, failing to perceive the truth of the situation, listens to and puts faith in such doctrines.... In this way he brings about the destruction of Buddhism and of the nation.” And the Lotus Sutra speaks of the “evil monks of that muddied age.” If these passages in the sutras are true, then there must unquestionably be evil monks in this country. The crooked trees are destined to be cut down on a treasure mountain, and dead bodies are rejected by the great sea. Though the great sea of the Buddhist Law and the treasure mountain of the one vehicle may admit the shards and rubble of the five cardinal sins or the dirty water of the four major offenses,34 they have no room for the “dead bodies” of those who slander the Law, or for the “crooked trees” who are icchantikas, persons of incorrigible disbelief. Therefore, those who endeavor to practice the Buddhist Law and who care about what happens to them in future lives should know what a fearful thing it is to slander the Lotus Sutra." - The Actions of the Votary of the Lotus Sutra

"The True Word school, among others, attempts to destroy the Lotus Sutra. It is essential to refute the True Word teachings, so in preparation I first attacked the errors of the Zen and Nembutsu schools..." -- Letter to the priests of Seichoji

Were it not possible to destroy Myoho renge kyo, there would be no rationale in refuting the various other teachings.

“Rely on the Law and not upon persons” and “[If a person fails to have faith but] instead slanders this sutra, [immediately he will destroy all the seeds for becoming a Buddha in this world]”? They must have been possessed by evil demons, or become drunk on the bad liquor of inner darkness."

"...He also states, “One who destroys or brings confusion to the Buddha’s teachings is betraying them. If one befriends another person but lacks the mercy to correct him, one is in fact his enemy. But one who reprimands and corrects an offender... rids the offender of evil is acting as his parent....” - Letter of Petition from Yorimoto

What are the seeds for becoming a Buddha in this world? They are only Namu Myoho renge kyo.

"The Lotus-like Face Sutra says: “The Buddha said to Ānanda: ‘It is like the case of a lion who has died. No creature that lives in the air, in the soil, in water, or on land will venture to eat the flesh of the dead lion. Only the worms that are born from the body of the lion itself will feed on the lion’s flesh. In the same way, Ānanda, the Buddha’s teachings cannot be destroyed by outside forces. But the evil monks who exist within the body of my teachings—they are the ones who will destroy these teachings that the Buddha has labored over and worked to establish for a period of three great asamkhya kalpas.’” - The Selection of the Time

"Answer: The Larger Wisdom Sutra records: “Shāriputra said to the Buddha, ‘World-Honored One, are the five cardinal sins and the sin of destroying the Law similar in nature?’

“The Buddha said to Shāriputra, ‘No, they are not similar. Why is that? Because if one destroys the perfection of wisdom, then one destroys the all-inclusive wisdom and the wisdom that understands every aspect of phenomena possessed by the Buddhas of the ten directions. When one destroys the treasure of the Buddha, then one destroys the treasure of the Law, and when one destroys the treasure of the Law, one destroys the treasure of the Buddhist Order. When one destroys the three treasures, one destroys all the correct views in the world, and when one destroys all the correct views in the world, then one is committing a crime that will bring one unlimited retribution. And when one has committed a crime that will bring unlimited retribution, then one must undergo pain and suffering for an unlimited period of time.’”

And elsewhere in the same sutra it says: “Because these persons have accumulated the causes that come from destroying the Law, they will fall into the great hell for a period of immeasurable hundreds, thousands, ten thousands, millions of years. These persons who destroy the Law will move from one great hell to another. And when the great fire comes that destroys the world at the end of the kalpa of decline, they will move to the great hell in some other world. Thus they will move here and there throughout the worlds of the ten directions. And during that time, though the fire will occur at the end of the kalpa of decline and they will die in one world, because they have not yet exhausted the evil karma acquired through the act of destroying the Law, they will return to the great hell in this world.” -What it Means to Slander the Law-

"...It will not be the non-Buddhists [but in most cases the Buddha’s own disciples who will destroy this Buddhist Law of mine].” - On Dealing with Disaster

"These evil men will read and recite this sutra, but they will ignore and put aside the profound and vital principles that the Thus Come One has expounded in it and replace them with ornate rhetoric and meaningless talk. They will tear off the first part of the sutra and stick it on at the end, tear off the end and put it at the beginning, put the end and the beginning in the middle and the middle at the beginning or the end. You must understand that these evil monks are the companions of the devil.” - The Opening of the Eyes

and later in the same work:

"Nevertheless, our merciful father Shakyamuni Buddha, when he faced his end in the grove of sal trees, stated as his dying instructions that we are to “rely on the Law and not upon persons." “Not relying upon persons” means that when persons of the first, second, third, and fourth ranks168 preach, even though they are bodhisattvas such as Universal Worthy and Manjushrī who have attained the stage of near-perfect enlightenment, if they do not preach with the sutra in hand, then they are not to be accepted.

Men and women such as SGI leaders, Nichiren Shoshu and Nichiren Shu priests, and the ignorant such as Jerry and Katie, all those who fail to preach with Sutra in hand are not to be listened to. Let us listen to the Eternal Buddha and Nichiren Daishonin exclusively