What fuse panel are you talking about--is it for the house loads, or is it the chassis fuse panel under the hood for things like the windshield wipers and marker lights?
I concur with your guess of a blown fuse or, failing that, a broken/bad connection in the 12V wiring. The 12V fuse panel for the house 12V loads is usually somewhere accessible from inside the motorhome, often ajacent to or a part of the 120V breaker panel. Whether the fuses are labeled adequately so you can easily figure out which controls the fridge is anybody's guess, but one of them would.
It probably would be worthwhile to do a quick check to see that the 12V ground connection for the fridge power is A-OK as well.