I'm not familiar with the specific model you're dealing with, but if you go to Roadtrek.com and register your unit with them (name, address, year/model, VIN), you could ask email@example.com
your question. They prefer you be registered, helps them identify the exact specs for the year and model, and they may have had a report of something like this one before. They could also advise you how to get at the plumbing, or if it's better handled by a dealer. Might be worth a go? I think I sent them a note asking how to register my 2002 C190P - I believe I sent the question/info to sales@Roadtrek.com
but it was a few years ago.
How close is the roof air conditioner to the leak location? Could it, or something else, be condensing the humidity in the air, and dripping near it, causing it to look like a leak? I guess the amount of water leaking is the answer to that theory? Did you encounter any (driving) rain during your trip? Perhaps a window or other (rooftop?) seal is leaking?
Wish I could be more help, sorry.
Good luck with it.