He claimed on the witness stand during the trial that the FBI was involved in the murders- and then later yelled at the mother that she was being manipulated by deep state agents.

Any suggestion that he's "admitted it was 100% true" are BS. He seems to be allowing (for now) that people really died and at least some of the families were not actors, which is an improvement, but he's not really caught up to reality yet.

A lot of the trial was spent trying to convince the jury that there was some ulterior motive behind the lawsuit, and he's been airing stuff suggesting that the judge and the plaintiff's lawyers are shadowy government agents.

I suspect a good part of it is that he knows and knew all along, but he made his money this way, and now his thought process is (rightly or wrongly) that if he acts like he sincerely believed it, then it's less evil to have said what he said because he was 'mistaken' and not a piece of shit.