If he were to say, for instance, "yes... I was at least partially responsible for those leaflets" (even if he was only responsible for having helped distribute them), and if he said he no longer holds whatever beliefs made it possible for him to assist in that kind of incitement to hatred, and he regrets that he ever did, it might be possible to trust that he does not now have a hate agenda.

He has not done this. He has only tried to obfuscate and mislead us into complacency about his agendas by making it look like he had nothing whatever to do with writing or distributing the leaflets. When people lie to me and try to mislead me, I tend to not trust them. I think we are getting the same old product marketed to us in a shiny new package. Our own white supremacist groups here in the US have tried that trick on us a time or two, and most of us don't fall for it any more.