[jimcol]

I might as well chime in.
1. You don't need a draw to reset a GFCI but you do need power into the outlet.
2. I'd follow Carls's recommendation only I would do it backwards. I'd apply a toner at the washer/dryer plug and follow the tone with an amplifier it will lead you to the next termination on the circuit. I picked a cheap one up at Loew's or Home Depot a few years ago for about $25 bucks but everything has gone up since then. If you know a phone or cable tv person they'll have one. It's easier than trying to visually follow wires in these RV's .