Wow, you have your hands full! Sorry you are dealing with all of this. Sounds like you already know what you need to do in reality, it's just putting it into action!
As for his daughter, is there anyway you could get him to sign guardianship to you, not give up his rights, but also allow it for you. That way if it came down to him leaving, which sounds VERY likely you would have some form of guardianship over her???