There are some (few and far between, and maybe not near you) MH collision centers that are experts in RV body/systems repair.
Failing that solution and not wanting to reuse your previous repair shop puts you right were you are, or where a majority of us would be in your situation.
Just do what you're doing, ask for references, investigate possible candidates, ask your RV insurance company for possibilities, etc.
Ted & Melinda
2016 ACE 27.1
2016 Chevy Sonic Toad
2020 Chevy Colorado Z71 Trail Runner Alternate Toad