There is nothing wrong with the 12 V reference (negative terminal) of your inverter to be connected to ground if this is indeed the connection that was removed. I'm relieved that there is only one such connection, for that's the way it should be.
The RV should be equipotential with the Earth. ie. It should NOT be able to be charged above the ground potential by lightning, etc.
In general, you wouldn't attach a ground rod to a trailer. The trailer is insulated from ground by the tires. The trailer NEEDS a ground reference when it's connected to AC.
Reminder, as I understand it, the 12V is supplied by the 120 V system.
One side of the 12V being grounded is a good thing.
The RV should be equipotential with the Earth. ie. It should NOT be able to be charged above the ground potential by lightning, etc.
In general, you wouldn't attach a ground rod to a trailer. The trailer is insulated from ground by the tires. The trailer NEEDS a ground reference when it's connected to AC.
Reminder, as I understand it, the 12V is supplied by the 120 V system.
One side of the 12V being grounded is a good thing.