[PNW Fireguy]

First don't bother taking the fan down to tug on wire. The romex is supposed to be stapled every 4.5 ft and within 12" of the box it is terminated in. Despite the fact that I don't think this is your issue based upon what you have shared check that your GFCI outlet is not tripped. They are not supposed to use the feed through for non-gfci loads but sometimes things happen. Also manually turn breakers completely off and then on. A tripped breaker sometimes can be easily overlooked especially with the trim cover for the PD distribution centers. The outlets in RV's are self contained devices (SCD) It's pretty hard to get the wire out of the connection points due to mechanical agitation when they are installed properly. The RV manufacturer's are probably the only folks that pay the $750 for the specialized tool to install SCD's.