I have had the exact same symptoms. They did rotate and balance until they found the bad tire, then they made it the spare.
I still have the wobble when I first take off, then at 50,60, and 70 mph. anything in between is fine.
Honestly though, as much rock crawling I have done, I would not be surprised if all my tires had a certain amount of damage.
But the halfshaft theory is interesting. I'll have to look that up.
I think you know that as far as warranty is concerned, half shafts and tie rods are never replaced.
But having you return it to stock.....that's just a dare....call HUMMER.