fortytwo wrote:
The roof is crowned, so the leak has to be on the shower (passenger) side.
No it doesn't. Water is a funny thing, especially when it is between two surfaces, like the sheathing and roof membrane or covering. I have seen a roof leak on a stick and bricks be on one corner of the house, and the water come through the cieling of the kitchen in the middle 40' away. RVs are the same.
Do you have factory maxxair vents/fans with the factory installed maxxair covers that attach to plastic eyes molded into the vent flange by chance?