^^I agree as to responsibility.
A question OP...is the J-wrap actually damaged, bent/kinked, or is the fitment just wrong, not allowing the baggage door to close properly? Can it be taken loose, adjusted for better fitment? Do you have a picture?
I'm thinking an alternative solution, pending severity, of issue/damage, the dealer/manufacturer may allow someone else (body shop) do the repair, at their expense, or maybe discount your purchase accordingly.
Frustrating for sure. Hopefully your dealer will step up and work with you, or you may try calling the manufacturer direct. You seem to be a sensible, and patient person, that can work with these people to reach a satisfactory outcome.
Jerry