@NickTransmissions - any thoughts on this?
My thoughts: Sounds like a *********** of immense proportions, lol. Agree with you and many others - why is this dood posting this instead of taking care of business with his wife when it comes to that poor vehicle.
As far as overfillig a trans causing his problems - yes. If any trans is overfilled to enough of an extent, the pump will cavitate and start to eat itself as the rotor/slide start to aggressively erode the working surfaces. This leads to a collapse of the line pressure curve inside the unit resulting in burnt clutches and torque converter. Not sure why the OP's wife continued to drive it instead of parking it/taking it back to the shop but it's none of my business.
Hope he gets a new transmission and torque converter (not a GM converter or he'll find himself back at square one before he knows it).
Interesting thread, to be sure.