There is Buddhist precedence of Nichiren calling for the death of evil monks and what this really means according to the Buddha and according to Nichiren.

"In the Anguttara Nikaya,“To Kesi the Horse Trainer” is about the Buddha’s conversation with a horse trainer on the similarities between training people and horses. At one point, the Buddha explains that if a tamable person does not submit to any training, the untamable person is killed. However, shortly after this statement the Buddha explains that death is meant as the Buddha’s abandonment of that person’s needs, thus meaning the death of the person’s ultimate potentiality (Thanissaro, 2010)." - From Buddhist Traditions and Violence by Michael Jerryson

Nichiren in his Establishing the Correct Teaching for the Peace of the Land explains that what he means about "beheading" the evil monks is actually "the withholding of alms to the evil monks". Likewise, I exhort Nichiren Lotus Sutra Buddhist believers to withhold donations to the evil SGI laypeople, the evil Nichiren Shoshu priests (monks), and the evil Nichiren Shu priests (monks).