HOWEVER, if your stbx gets the house and fails to make the payments, you may never learn about it until your credit is ruined.
I would suggest:
1. Ask for a clause that stbx must refinance within 90 days or put the house on the market at a price selected in advance (or based on x number of appraisals or whatever - just don't say 'put house on market' because they could put a very high price).
2. If that won't work for some reason, insist that you get copies of the monthly statements. As soon as you see a payment has been missed or you don't get the monthly payment, go to court to have stbx found in contempt.