You could do this, but you may still have do deal with Pay-Pal taking money out of your account. You cannot close your accounts right away either, you can close the funding sources tied to your Pay-Pal account, but your credit score might take a hit if Pay-Pal reports you for an unpaid bill.
I would get back on the phone with Ebay and raise hell once you get the lens back and know the condition. Unscrupulous buyers pull all kinds of scams on honest sellers, and there is no way to leave bad feedback to let others know.
I am all but done selling on Ebay, since it's not worth the hassle and fee's. Good Luck
I don't think you can close a funding source whilst there is a transaction involvement of any kind.