What do you when dealer misdiagnosed problem with ac have no parts to fix it. I carried Georgetown in 3 weeks ago after trip to Key West and ac quit working. They said compressor was bad and ordered new compressor. I was called and told part was in and bring rv in for repair. It sat there for a week before it was put in shop. New compressor put in but was not problem so they took it out and put old one back in and say it is a control panel. I have campground reservations stating tomorrow for week end.
Unfortunately not much you can do. You can camp with no A/C or cancel. It is never fun dealing with a situation like this but sometimes it happens, make the best and learn from it. Sorry.....
Another issue is that when a compressor is removed the likelihood of it failing in the future goes way up. You could always suggest to them to take the board out of a unit on the lot so yours is fixed and they can put the new board in their unit.
I had a similar situation. I was told it was the thermostat. A new one was put in and problem not fixed. I didn't get to try it out before going to the beach. Got to the beach and. ......no air. Contacted dealer and they said it was control board. Called camping world and they had an upgrade kit for my unit. I had to figure out the wiring but it works. If you are handy maybe that would be a solution for you.