Might be the TIPM
Both me and my girlfriend have 2009 KK's. I haven't had any problems with mine but she had a problem with her window switches. They stopped working the other day. The dealership said that the TIPM had gone bad. This is apparently part of the fuse block area under the hood and stands for something like, "totally integrated power management". When this goes bad it can affect various things such as the window switches, dome lights, dash lights, radio, etc. It might affect one thing, not another, or all of them at once. A few months ago her radio went out as well but the dealer just replaced the radio. Maybe it was the same thing? She apparently tried to adjust the dash light dimmer the other day and then the windows stopped working. I was curious and asked a bunch of questions in case it happens to my KK.
The mechanic may have replaced the switches and then realized it was the TIPM later thus taking 3 hours to repair it?