Doesn't REALLY matter to me. But at auction it takes at least two to tango (unless sold at opening bid) so wouldn't the "real" value depend also on what the under bidder would have paid if correctly described ?
Splitting Hairs and playing devils advocate.
I NEVER offer posters to the underbidder at any price, for this exact reason. If the high bidder does not pay, I re-auction the item every time.
But this is a different situation. I auctioned a poster for say, $100, and much later learn the poster is a re-release. Most often, the buyer either returns the poster and I re-auction it (properly identified) and I remove the first result from the Auction History, and put the new result in after it is re-auctioned. Or they say "I still want it" and the result stays, properly identified.
In rare cases they say "I would keep it if you would refund $40" (or whatever amount). If I think they are being fair, I refund them $40 and adjust the price to $60, Yes, by splitting hairs you can say it technically did not auction for $60, but the buyer did pay that, and it is one result out of 912,000+, and it DID sell for $60.