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Find another dealer. The Pirelli flat spot problem isn't initaited by a bump in the road. That sounds more like a bad strut/shock. For the flat spot issue, putting an extra 5lbs (40psi total) in the tires generally gets rid of that problem.
bridge, the only issue with that remedy is here on the SoCal freeways at 40lbs pressure the road surface will shake you to death. We are lucky though as it doesn't really get that cold so the flat spotting is only a minor issue and only if I've left the truck sitting for 3 days or more.
To the OP - have your dealer's service writer ride with you in the truck and demonstrate the problem. Then (if necessary) have the tech ride with you as well.