I would call your SA and tell him just what you stated here. You really have no motive to lie at this point as you have already told them you'll take responsibility. Hopefully they will just absorb the damage because it was not that serious nor was it the result of obvious negligence or abuse. Also, they have to expect some dings and scratches to their loaners.

I think that if you state your case as you did here and throw in my last couple of points the dealer will realize that the loss of you as a client worse than having to make a minor fix.

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