Sorry Phil, that contention is so unproveable it is amazing you are still pushing it. There is absolutely no proof. Yes I have seen the many of the films, read the articles, and listened to the presentations of several groups claiming to have absolute proof.
Netanyahu: Most of Americans see eye to eye with Israel on dangers of Iran deal (Haaretz)
from the article: Reputed 9/11 mastermind says he decapitated journalist Daniel Pearl