Buyer (me) sold gift cards with 0 on the balance.... best course of action to get money back?

I've heard of this scam the other way around but I haven't had much luck searching and finding buyers who were legitimately scammed on gift cards.

I purchased several gift cards from a seemingly legit seller, perfect feedback, and initially all the cards had the correct balances. 3 weeks later they disappear. These were never mailed to me, but emailed to me btw... electronic delivery, which I know is a big no no on ebay.

Do I tell ebay I never received the item or that I want to return it or do I go through paypal to dispute? We are still within 30 days of the auction ending. I dont want him to throw some more zero'd out giftcards in a mailer and upload the tracking and win the case.

What is my best option here?