It maybe just as easy to fix the roof that you have an alot cheaper. When you peel back the roof make notes of what you do, so you can do it in reverse. You took off your ladder because of looseness on roof. When you peel back roof to check where mounting holes were, you may find just a poor location with no backing for screws for ladder. Place a 2by2 or what ever the thickness of stud fasten to existing stud, for new ladder support. The ladder will be useful to check roof seals, checking air-cond, ant or just storage. When I fixed my sons slide-in camper we had to put in a roof support under his metal roof, it was older than your camper.
Its a good idea to use gloves working around metal. Just take your time, have a tarp handy in case of rain, use new holes an sealents as you put roof back together. Extra hands mite help also. HAVE FUN
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