I knew you'd ask.
I mounted the controller on the fascia is behind the door in the compartment above the refer after I found that there was nothing behind it but space. Though it is not completely sealed from the inside of the coach, to prevent any refer venting issues, I drilled two holes for the wires in the fascia and mounted the controller in a surface mount box with about a millimeter of space for the compartment door to close. The holes were then sealed around the wires.
The heat issue is a concern, but the thought is that I will leave the compartment door open if there is any question about the heat, leaving the controller near the A/C flow or the rear Fantastic Fan.
We're weekenders mostly, so I think I'll be fine. If not, I have a 12V
low speed, high flow (but silent) fan from an old power amp that I can rig up somehow to increase flow.
This location was about the only realistic option without major work.