Class C overhead movement causing seal failure

When you look at the point just above the windshield where the overhang meets the chassis cab is there any sign of separation there? Or is the seal nice and tight?
If there is separation, the overhang is no longer attached to the cab. Not good.
Time to get up in the bunk and start removing stuff until you can actually see how Winabago attached the overhang to the cab.

As far as the split, as long as appearance is not a concern, EternaBond would be a decent fix because it will flex.