You guys keep telling me I am wrong. So I will ask of all of you again.
A GFCI trips because there is more current flowing from the HOT pin into a load than there is flowing from the load back to the NEU pin. That creates the required imbalance in current required to trip the GFCI. It also means that difference in current has somehow been diverted out of the normal flow path. Now where did that current go? Current can ONLY flow to/from the initial power source, i.e. the required “closed loop”. A most basic principle of electricity. That means the missing current has to have an electrically conductive path back to that power source. If the RV is not grounded to the generator, where is that required path? That current can not simply disappear.
This is a simple question that no one seems to want to address.