For buyer (and seller) protection purposes, eBay treats even attempted delivery as having been successfully delivered.
Whether they will do the same as evidence of delivery for payment release only eBay knows. Their new buyer protection fee has created so many problems and complaints that I doubt if even eBay customer support has all the answers.
Personally I would wait it out for the 14 days. The good news is that if the buyer opens a money back guarantee case for non-delivery you should win if the tracking states that delivery was attempted. But even then eBay may drag it out to allow further time for the item to be received. eBay is in a muddle of their own making.