I'm not sure what, exactly, happened to cause the RV owner to not be able to operate some things. Did the breaker for your 50*amp power outlet trip? Did the wiring on your side of the outlet burn up?
Wiring will try to conduct whatever current is drawn through it. If the RV is drawing more current than the breaker or wire can provide, either the breaker will trip or the wiring will burn up.
The power should be provided by a single 50-amp 2-pole breaker. This guarantees that the two legs of the circuit are 180* out of phase, as they should be.
If both legs are on the same phase, that could cause problems.
Wayne
