I don't know how the rules in your country are precisely, but here, the watch would have already been your property eventhough you hadn't picked it up yet. Therefore the AD wouldn't be allowed to let others wear the watch. I don't know if you're willing to go on the legal route with your AD, but maybe finding a ground that proves that you're in the right might convince them to cover the costs of buffing or polishing the watch.
Edit: posted this before I saw the situation update, but I'm leaving it here for others that might be in the same situation.
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