I would bet the banks are gonna balk big time… they are taking second behind a first that you as the “owner” aren’t even liable for.
I know if I were a banker, I’d tell you no way, but if you like Mr. “owner” we’ll gladly offer you a new first mortgage that will allow you to pay off the first, and put cash in your pocket.
I believe some lender may do this but it is unlikely. Your better option would be a cash out refi or it is possible to get a 1st position HELOC for 80% if your score is 680+
Email me if you need more info