Contact that lawyer and get this guy into trouble for forging your signature! He could find himself in some real hot water over this issue. I don't think the army takes kindly to forgeries... also, if you show you were not "legally" divorced, he would seem to be guilty of polygamy??
Also, it seems like there should be a much larger amount of child support coming directly from the government out of his pay...
Go after him for a lot more! If he doesn't pay up to have your refinance done, and other things on your terms, let him suffer the consequences. He made a big mistake by forging that document.
If you let him get away with it, then maybe he was right in thinking you a fool?? Of course maybe a little tact needs to be used by telling him if he doesn't fork over the dough, then you'll pursue criminal charges based on his illegal activities? A lawyer would love this, and wouldn't it be nice to force him to pay for your lawyer too!!