Don't feel sorry for him, he sold himself out.
I do feel bad. lol I realize it is a little naive but I do feel that way and not just for him but some in the past as well. I don't like the evil ways of how MF operates. His contract might have said he had to agree to stay until Ali dismissed him. Do I think he literally had a gun held to his head? Of course not. Do I think he can be pressured, threatened and manipulated? I do. I think MF knew long before Frank was F3 that he wanted out. I trust RS on that.
Could there be a deal in place for money? Of course. Perhaps he agreed to give them reunion footage they wanted in order to finally be released. Could be a sell out or he might have been desperate enough at that point to do anything to get out. I don't think Frank is 100% innocent in all of this but I don't see him as a huge villain either. He didn't want to be with her and she doesn't want to be with CL and Roberto. Their choice in the end.
I wonder if after it's all said and done if he will wish that he just let it play out and deal with it all after show was over.