sounds like you have lost several of your big ticket circuits. The MW should be on its on breaker so for sure check it by flipping to ensure its fully off...then back on. The HW tank should also have its own dedicated 110v breaker, do the same with it. So the GFCI in the bath is not powered...have you hit the reset on it already? There may be another GFCI on the unit elsewhere in a wet bay or ??? If its an actual GFCI in the bath and its dead then the problem is back at your panel. There is definitely a gremlin in your system somewhere, and its hard to trouble shoot from afar. Was your dealer RV city in Morinville? If so, or no matter where it was bought a ten minute call to a tech there might just put you on the right track. Better be prepared to open up the panel, test everything on the panel and converter etc. Im sure your not laughing now but I wonder if its not something simple were all missing.
Daryll