You will find that the rolled edge portion of the roof falls under yearly maintenance.
That rood portion is held down by the caulk where roof meets side trim. You will need to clean the old caulk out (might as well do whole side) then apply new caulk made for the purpose of holding down the roof. I use Sika https://automotive.sika.com/
If you go over to the winnebago owners forum theres lots if info on your problem
https://www.winnieowners.com/forums
Itasca Meridian SE 36g
Road Master Tow Dolly