First of all did you buy this new or used?
What type of warranty did you have on the MH?
Thor did pay to have this fixed,
but not before they blamed the damage on me. I
installed a super steer track bar
Sounds like you did in fact install an aftermarket item yourself. They diagnosed that that is what twisted it. They repaired that AND did NOT charge you for something you created. I'd say that was pretty fair if not exceptional.
They added a leaf spring to both sides.
I had that done to my MH. Yes it made the tail end of the 'body' of the MH up a little higher. Eliminated bottoming out and stabilized the handling.
Adding leaf springs does NOT change the height of your MH chassis from front to back. It only raises the body. So your claim you have to level it while parked on a level pad because of the added leaf springs is just not correct.
It seems that Thor and Ford have gone way beyond to fix, and make numerous repairs on your MH and at no charge to you.
Are you a first time MH owner?
How much cargo weight do you have inside this MH?
Where is it located in the MH all in the front or all in the back?
How old are the tires?
Do you have the correct air in the tires?
Most of us keep the front tires a little lower in air than the rear. Too much air in the front tires will have them bumping around which mimics front end handling problems where just lowering the amount air in the front tires rectifies it.
These are just a few of many items that can also affect how good or badly a MH will handle.