My 2018 Cougar has some delamination going on with the fully fiberglass cap. Looks like they screwed up the resin mix somehow. There are raised areas or bumps in a few places, very hard to press them down.
They had the nerve to say it could be due to water damage from a bad roof seal !
The darn cap is 100% fiberglass, you could throw it in a lake for a month without hurting it.
I'm trying to get a completely new cap from Keystone, my fear is, sure they can grind down the blisters and do a good job repainting it but I'll guarantee you more bumps will appear later on down the road. And we will be playing wack-a-mole for the life of the camper.
Reminds me of the time I had an old sailboat, it had blisters on the bottom of the hull. I spent 3 weekends with and angle grinder eliminating them. Then had to lay another layer of fiberglass cloth with a barrier coat, fun times.
Ron W.