No, breakers should be inside somewhere.
It's seems odd to me that the microwave and another receptacle would go out at the same time since I believe that code requires the microwave to be on its own circuit. I could be wrong.
Could be that a wire became disconnected somewhere. I would start by disconnecting from shore power and removing the breaker panel and checking the wires at the breakers. I would also find where the neutral wire buss is and check those wires as well.
I would also remove the receptacles and check the wires there as well.
Blue Mound State park, nice area and the tallest spot in southern WI.
Chilly this morning.
Peace
Dave