Welcome to JOF...., but sorry to hear about your moisture damage.
Your correct about calling the dealer first, this way possibly the root cause can be found ASAP.
I would focus around the window seals, roof/front cap seam, and the A/C seal above the window. Also, marker lights are noted to be possible moisture entry areas.
2016 GM 2500HD 6.0L/4.10
2005 Jayco Eagle 278FBS
Reese HP Dual Cam
Putnam Class V