I haven't heard of any changes in the transmission of the Edge, and lot of folks are towing them. The only thing I've run across is the full on digital dash has confused a few because they can't turn it off when towing.
Our 08 AWD is pretty simple, turn the key to accessory (to unlock the steering), put it in neutral and go. The book does advise starting and shifting it through the gears before we tow.
You have my interest peaked, .... I sure don't want anything close to what your going through. Thankfully they have replaced your transmission, but being without something like your vehicle for extended shop works sucks big time!