Well...... Our Story is Done (for now),
After removing the bed platform I found that there is a mixing valve at the hot water exit from the tank...........only God knows why. Disconnected the cold water tube from the valve, capped it off, and amazingly we have hot water at taps. This valve probably needs to be removed, but I don't want to do while on the road. I have to say, I'm very disappointed in Fleetwood for not knowing about it, and for installing it this way. Thanks to all who tried to help us.
Chuck P.