I hope OW returns as she probably provides a measure of safety for your son.
Most WASs are lousy at getting their paperwork done - it's not the zipless divorce they expected where everything falls into place with zero effort on their part. I hope he doesn't hold it up too long and that your financial settlement is not affected by the delay in any way? I never understood letting the finances be settled before the divorce, it removes the motivation for some people to finish it.
Aren't you glad not to be at the whim of your ex's financial irresponsibility any more? You have a good head on your shoulders and will much better off financially in the long run, I'm sure.