RV GFCI recent AC problem

Everything was fine in my RV until I went in it this past weekend. I have been in it for three days straight trying to figure out what is going on. If anyone has any thoughts, please let me know. It started when I tried to plug something in to an outlet. The GFCI that serves the outlet keeps tripping. Here is what I found out so far from troubleshooting as I thought I had a neutral to ground issue. I am still not sure what problem I have.
1. If the RV is not plugged in to the shore power or onboard generator, the neutral and ground in the power distribution panel shows no continuity. I believe this is good as I read the RV should be treated as a sub-panel and should not be bonded between the neutral and the ground.
2. When I plug the RV in to the shore power, the RV panel shows bonded between the neutral and ground. I assume this is normal as the outlet that it is plugged in to is coming from my main house panel which is bonded.
3. When I plug something into the bathroom GFCI, it works.
4. If I plug something into the outlet that is connected from the load of the GFCI, it trips the breaker.
5. While this breaker is tripped, the following breakers in the RV still work:
The kitchen GFCI outlet works and things can be plugged into it with no problem.
The outlet that runs the microwave is working and so does the microwave.
The refrigerator works on AC.
For the life of me, I can not figure out if there is no neutral to ground problem when the RV is plugged in. Why does this outlet trip the GFCI?
Just for kicks, I ran a new line wire from the panel to the bathroom GFCI and tried to plug something in the load receptacle. It still tripped the GFCI. This tells me that there might be a problem after the GFCI on the load side. But wouldn't it show up as a neutral to ground continuity? Also, if I don't plug in anything to the outlet and just connect the little yellow cube tester to show if it is wired correctly, it shows that it is wired correctly.
I even plugged the RV into the generator and tried everything using generator power and it still blew the GFCI.
The last thing I thought was maybe the generator wiring was messing with things. But I thought if that was the case, why would only one outlet be impacted and not the entire RV. I have one 12 volt storage battery also. It seems to be working fine as it starts the RV. There is a foot of snow on top of the RV. But I don't think there is anything up on the room that has any wiring exposed that could be messing with things.
Any suggestions as to what to test next? I am now at a loss for what to do next. Thanks in advance for any suggestions.

 

Also, to eliminate that the GFCI could be faulty, I replaced it with a new one today. The same thing happens. Again, at the end of camp season, everything was working fine.

 

OK, have you ever done this? Something bugs you so bad that you can't sleep? I had my pajamas on and back off three times since this post. I am 99.9 % sure I found the issue. When I went back in the RV and put the yellow cube type tester on the outlet in question, it showed "open neutral" I forgot about one last receptacle. It was outside of the RV. When I plugged my tester into this outlet to see if it was showing correct, it came up with "open neutral" and then if I jiggled it back and forth it would either say "open ground" or the center light was bright and the outside one was very dim. I took the outlet out and the black wires were in good shape but the two neutral wires were green and were loose in the back of the receptacle. All of this after I literally tore the entire RV apart looking for the problem. At least I found it. Will replace tomorrow as it is dark and 23 degrees. Not the best conditions to do a quality reinstall. I thought I would share the outcome as someone else may run into this issue.

 

Good job wes... Welcome to the forums...

Sry no one responded to help but you were quick with the replies.... lol

 

Wow....repairs in one hour. You're good Wes.

Normally, the outside receptacle is the end of a circuit.