Can I go back and get my son?

I live overseas with my husband who is stationed here. I have a son from a previous relationship and he is with his father right now back stateside. My son's father opened an investigation on my husband for child molestation and it is obvious he is doing it to keep my son from coming back overseas with me. My husband has been investigated to the fullest and has taken 2 lie detector tests and ped both. I am a stay at home mom and almost never leave my children, so I am positive this did not happen. What I am wondering is if I can go back and get my son? We have an agreement in place that says he is supposed to be with me right now, if I go back with the agreement and an officer, is there anything he can do right at that moment to stop me?