2016 Aerolite 282DBHS bent frame?

[todbadriver]

I bought a barely used 2016 Dutchmen Aerolite 282DBHS travel trailer in 2016 and have used it a LOT for family camping each year since. I have modified the trailer a lot with the most substantial mod being I replaced the small door in the back with a normal-height solid door, requiring cutting the fiberglass and one verticle aluminum stud which I reinforced by using that cut stud secured for the width of the new door. I've had the slide adjusted by a trusted repair shop once before but after breaking a leaf spring on my last trip I took it back to have everything looked at and repaired as needed. They told me my frame is bent, as the floor at the rear of my slide is .75" lower than at the front of the slide. He can't find where it could be bent without doing about $5-6k of work tearing it apart. Everything looks normal on the camper...No fiberglass stress or doors closing as if the frame has moved. Has anyone else experienced this with an ultralite trailer and if so what is the best way to move past it?

[trucking]

I would get two more shops with excellent reviews to inspect your frame.
Ask them if .75 different measurment would be a problem.
Those frames do flex.
Happy trails, PJ