You mentioned in an earlier post that Canada Post had sent you 2 cheques for the insured value of the item. Why not simply cash the one that applies to the buyer who refused to repay the refund?
You are not defrauding Canada Post, since they failed to meet their commitments and you were obligated to refund the buyer, i.e. you have still suffered a loss as a result of CP's (via USPS) failure to deliver the parcel. The fact that the parcel ultimately showed up is irrelevant -- the insurance claim you made prior to that point was accepted and paid by CP, and you had already refunded the buyer in good faith.
With respect to the 2nd buyer, I would hold on to the CP cheque representing the insured value of that parcel and wait say, another 2 weeks to see if the 2nd buyer responds with a repayment of the refund you made to him. If not, I would cash the CP cheque.
Should the 2nd buyer suddenly have a fit of honesty and repay you, if you feel compelled, you can return the value of the insurance payment to CP. That would be the strictly correct thing to do, although I doubt CP would ever follow up, and I think they'd be rather confused, frankly, if anyone approached them to repay in this way.
In my experience in many years of legal claims involving insurers, most insurers don't care what happens once a claim has been approved and paid out (for instance in cases of theft of property from a home where some property may ultimately be recovered). The file is closed as far as they are concerned unless there is some indication of deliberate fraud on the part of the claimant -- such as claiming insurance for something one knows isn't lost or stolen, or where a highly valuable article (e.g. irreplaceable painting) has been stolen and may be able to be subsequently recovered.
I wanted to also clear up what seemed to have been a misunderstanding in this thread -- Canada Post does not provide an on-time guarantee for Expedited to the US. Those guarantees are for Xpresspost and Priority only. It does so within Canada though. See the charts at these links:
http://www.canadapost.ca/web/business/mailing-and-shipping.page
http://www.canadapost.ca/web/business/mailing-and-shipping.page
For this reason, CP wasn't obligated to refund you for the shipping cost, although in my view it would have been the proper thing for them to do in this situation, considering it was a tracked service you paid for.
IMO you took all the proper steps. By the way, to clarify the legal arguments vis-a-vis fraud, it would only have been fraud to make a claim to CP for loss after Pierre was correct in reacting as he did to a suggestion that a seller should look into making a claim after the item was already in the buyer's hands.
However, you made the claim while the parcel was still MIA, so there is no problem. Even if you hadn't made the (insurance) claim when you did, in this situation I would still have contacted CP to let them know the situation and to tell them you had refunded the buyers. There would have been nothing dishonest about that.
You're absolutely right though -- eBay isn't helpful in these sorts of situations.
