I am sorry; I don't know what advice I can give you on the legal end. I haven't lived it like others have here. I do have a feeling he is going to show-up, paper signed or not. It is just a feeling.
To you STAND YOUR GROUND! YOU HAVE CHRACTOR. Think about how for you have come. The hard work you have put in to your sitch. You can do anything you set your mind too.
I truly wish I could say something that would give a road map to your destination. My crystal ball is foggy on this one, but I have total confidence in you having the strength to face this next visit with the same intestinal fortitude you have handled all the other hurdles.
You will be great Take a deep breath and get after it.
