We have had a leak under our shower since we purchased our coach.
I have an endoscope and could see the problem but there was no way that I could fit my overly large hand(s) into the access panel!

The nearest authorized dealer from our home is over 100 miles.
On our trip last week we camped about 5 miles from Camping World in Holiday, FL. when we called for service, of course, they wanted us to bring the coach to them but after we explained that we were "on the road" and could not drop the coach off for them to fix, they scheduled a mobile repair appointment.
The two techs they sent were "in house" technicians and did not normally do mobile repairs. So they did not bring their very large shop endoscope! I offered them mine and they were amazed at the clarity for such a small unit. (See low resolution pics.)
They could see the problem and went to get the parts needed to make the repair. They had to cut the pipe from the grey water tank and put a new fitting onto the pipe so that they could secure the Waterless P-Trap properly.
As an engineer, it is obvious to me that the issue was caused by factory personnel over-tightening the Black ABS fitting when attaching it to the PVC waterless P-Trap. The problem was fixed in short order but never should have happened in the first place. I'm sure that if I had been able to take our coach to a local authorized Forest River Service Center they too would agree.
For reasons unknown to me, the access panel is toward the left of the shower and very difficult to access in any case. I would strongly recommend that they add a second access panel to the right of the shower, which would allow repair personnel to use two hands when fixing this type of problem.