Pale, that's encouraging news. Now, proceed with caution so that you don't get caught by manipulation. I second what someone else said here before ... I think your GF is a bit reckless to get involved with a man who is only 4 months recently separated, with a child and the cult history behind it. You are a ticking time bomb now for her. Don't break her heart.
As for your wife, and based solely on what you said, it may well be that she is now seeing the WTS with different eyes and realized the monstrosity of the condition she is trapped into now. But she may just be manipulating you to keep you "close" as an option in her life, in an attempt to break your new relationship, so that you can remain available for her if she so wishes to leave the cult. Be careful not to be a mere option on someone's life and not the first choice. Remember that not long ago she chose her religion and her family over you. It could happen again, and her being overly concerned about losing friends and family is natural but also is a red flag, because, as it was said, she isn't emotionally reliable. I would consider a sure sign if she expressed concern about not exposing your child to be raised in the toxic environment of the cult, but has she expressed such concern? Or is she just worried about what SHE might lose?
You have some tough choices ahead to make. Be sure to make them in YOUR best concerns and those of your child - not necessarily your wife's wishes. If you truly believe your marriage is worth saving, you must act now so that you don't break someone's heart and wreck another life. If not, be supportive to your "ex" but keep a safe distance. Remember it's not your responsibility anymore.