I had the same type of problem on my 2004 Georgetown. The upper corners of the rubber moulding on the windshield pulled away from the body. Since at that time it was still under warranty, arrangements were made for a service person from Duncan Glass Systems ( they do glass work for Forest River in Elkhart) to our location in Fort Myers, Florida. He repositioned the windshield, sealed and shimmed the bottom of the glass so it wouldn't move.....this caused the separation of the moulding from the body. Apparently many openings for the glass are too large, thus too much movement. You might contact Duncan Glass. Sorry can not find a phone number but they are in Elkhart Indiana as well as other locations in the U.S.
Leamington, Ontario, Canada (now in Weslaco Texas)