The old thread was locked and I still have a few more pages to read, but (and maybe I'm just a hard ass) I would never accept him back in the family if I were them. Regardless of whether or not Smeg is manipulating him, I just do not understand how anyone can actually turn on their own family the way he has, especially since they always had a good relationship. I can't even be mad at Smeg. She's just being herself. Harry is the one who went along with it. I don't care if he looked uncomfortable during certain parts of the interview, or if he didn't know exactly what she would say. He had the opportunity to set the record straight. Instead, he not only went along with it, he twisted the knife a little deeper with the "my father and brother are trapped" crap. He did all this while he knew his grandfather was dying. He is a piece of dog shit as far as I'm concerned. Who cares who's manipulating him to turn on his family? The fact that anyone is able to should be concerning. If it wasn't Smeg, it would have been someone else.
Besides, as many on here have pointed out, he probably always had these feelings, but Smeg was a convenient excuse for him to be able to finally let them out. It reminds me of a joke a comedian told one time about meeting a famous comedian. He tried to talk with the guy, but the famous comedian just walked away from him. Another comedian told him that "he's just shy". The comedian telling the story said he doesn't buy the "just shy" excuse. He thinks that @$$holes have been waiting their entire lives to be famous or rich so that they're free to be the @$$holes they've always wanted to be. I think that definitely applies to Harry.
Anger does eat away at your soul and your peace of mind, so by all means let the anger go. But don't accept Judas back into the family. Wish him well, be there for him, but keep him at arms length. Even that is being more generous than I would be. There are some things you just don't do and can't come back from and that's betraying your family.