I was referring the the shore power, source. But, yes in your RV with a 50A, 4 wire shore power, you do have 240V into your electrical panel, where it is split to feed 2 circuits of 120V, (you are correct. your outlets are 120V, unless there is a 240V appliance, ie some dryers, heaters, ovens/stoves. We have 240V dryer, so that one plug is 240V/20A).
The only time the voltage would be different, is if the CG (shore power source) is a 120/208 Y transformer bank system, then each RV pedestal would have 2 - 120V phase to neutral and 208V phase to phase. But very few CG's have that type of setup from the utility, though I have come across a few in the south.
The point I was trying to get across was, if there is any reading from the neutral to the ground and the reading from phases to neutral are out of balance (more than a few volts) with a load on in the RV, they have a broken or loose neutral connection, inside or outside. You never are to have any voltage reading between the neutral and the ground, that is where folks get electrocuted. Actually, it very well may be just a loose connection that over time has become burnt and corroded. Simple fix, clean it up re-apply a small amount of penetrox and re-tighten, (with ALL power off of course!!!!!).
Most important!! As I said before, if your not sure or this seems confusing, don't do anything, call an electrician that is licensed, not just a buddy that "knows about it"!
Hope this helps and God bless,
Mike