Bobby,
When it's dry and safe, give the roof the best "look over" that you've ever done. Look for any seal voids, no matter how small. Inspect all sealant around all vents, antennas etc.
Water that gets in from the roof or high up on the exterior wall can run out far away from its entry point. As your roof tapers towards the back of the coach, water that has gotten inside the ceiling/roof structure can travel down this pitch, then finally down a stud and out through the interior wall decor panel.
Sorry to paint a bleak picture. This is worst case. You may have a simpler issue. But do start looking for the entry point.
For you and anyone reading this, no matter what brand of RV owned, a useful test that can be performed by dealers and services with this gear:
Sealtech USA