The problem can be corrected. The issue you have right now is who is going to pay for it. Even an altered or bent frame can be repaired by a competent alignment shop that has the right equipment and the mechanics that will take the time to do it right. Unfortunately, most RV manufacturers, and factory warranty issues are usually done using the least expensive solution, which may or may not work.
There are only a few places in the country that I know of will do the job right, but I doubt if Thor or Ford will want to pay for the fix.
One shop is
Hendersons and another is
Champion and a third is
Brazels and the last that I know about is
Sunshine Alignment. Just remember that you are looking for a shop that will correct "Thrust Angle" alignment problems with a truck chassis and that they have the equipment to accurately measure the before and after alignment.