Contact Jag, the Red Cross, his CO, chaplin on base and/or Family Services. This money is paid to his specifically for the family, the military does NOT mess around with this. Keep bugging them. Tell the ex you're not going to mess around with him anymore. If he has any sense at all, he will know he's going to end up in the brig shortly.

If it were me, I'd notify his CO (base CO)first. Politely explain that you are at your wits end and are planning on contacting the above along with your senator's and representatives (state AND federal) They really do not like to mess with family issues. Even if you don't have anything set legally, his CO is going to tell him to get his family baggage taken care of NOW. You can get the email addresses for senators and reps online. As I said previously, his status as active duty gives you avenues that civilians do not have.