1- does the rear driver window cant be moved by the individual window switch in rear as well as the driver master switch ?
2- the window motors can be checked by taking door panel off and applying straight power to them . if they work , than i will suspect the master switch to be the issue or the wiring not the motors , it is a simple test to do, maybe 25 min to take panel off and get to the motor /window regulator .
3- now as far as both motors going out at same time , unfortunately yes it does happen ,especially if those window are used more than the others .
if your husband have the know how and messed with electrical components before now then he can do the testing , if you dont want to do it , you can simply take to shop and tell them to test that way , i m sure they do it all the time , if it turned out to be the master window switch driver side , then get one of ebay ,be the cheapest, you can even find them oem new on there, not necessarily used ones.
my advice will be a new one , since most fail and the new ones has upgraded parts .
please let me know
ASE Certified Technician