Camping World may not have given you the entire warranty story.
If you had a hitch installed and had a warranty problem they would have to prove that what you did caused the problem.
So if, for example your slide fell out on the ground, the burden of proof would be on them that your hitch installation caused the problem.
It's spelled out here in the
Magnuson-Moss Warranty Act.
And on a side note, I had a frame problem two years after the warranty expired. I have a rack on the back of my coach and a receiver hitch mounted to my pin box. There was no question when Heartland/Lippert repaired it for free.
Peace
Dave