Note the 'if his accusation is false.'
Anyone who believes that which the NOI affirm as the central tenets of their theology is not a Muslim, this is a simple and straightforward fact and I have no idea why you would be arguing against this as a fact.
If he repents and affirms the Five Pillars and the finality of the Prophethood and the Resurrection (because they don't believe in life after death, which is contrary to the Qur'an) and the rest of the things he's gotten so abominably wrong, then he's a Muslim. Until then, he's not. Very simple.
What's interesting is that you keep talking about the videos over and over as if they're the only things he's ever said. What about, oh, I don't know, all the other things? Just look on the NOI web site. Just look at his writings in The Final Call! This is an absurd discourse. I am interested in your linguistic and historical analysis of the hadith, but embrace of Farakkhan is ridiculous.