I think the best play here is to ask nicely if they'll warranty the rear wheel for you or maybe rebuild it.
If they refuse to help you, then raise hell and ask to return it on the basis that you were clearly informed that the bike would hold your weight.
It sounds like a botched factory job to me. There's no reason for the wheel on a Trek 1.2 to come out of true like that.
Meanwhile, make sure that rear tire is inflated at max pressure every time you head out. At 270, if you ride at anything less, you run the risk of banging up the rim while you ride.
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