Kindly ask for pictures first, of both item as well as packaging. Ask that the photos be sent thru your Ebay email. Then if the buyer opens a case you have a better chance.
I have had more returns in last several weeks than ever before and I personally can not keep buying off the buyers.
If your pictures show there is no damage then stand your gorund. Ebay takes into consideration if the buyer has done this before as well as their feedback history. Not sure how this buyer ranks nor your investment but go with your gut.