x2 on pulling AC out, investigate what really happen before taking future action.
I have 2 TC both 17 years old and both hold the AC just fine.
Lance is famous for having single piece metal roof and with good seals around openings it holds very well, although ugly.
Fleetwood has rubber roof and that gave me some headaches at trims, but again, no structural problems.
I think if the problem is structural, you might be due to pull the roof out and rebuild/reinforce.
There is new roof coating at Home Depot.
White silicone stuff, that cost over $200/bucket. I applied it on my house roof 18 months ago and it holds very well, so Fleetwood roof waits its turn.