I think you’re over thinking this. The buyer may have been an eBay member for many years and still not have feedback, that doesn’t necessarily mean they never bought anything. It just means the buyer hasn’t exchanged feedback with anyone.
eBay allows buyers 4 days to pay for their purchases, on the 5 th day if the buyer still hasn’t paid you can cancel citing didn’t pay, the buyer will get an unpaid item strike. Then you can add the buyer to your blocked buyers list and relist your item.
To prevent further nonpaying buyers, I strongly suggest adding immediate payment required to your listings and if you have the buyer requirement to require buyers to provide a payment method before submitting an offer, I suggest you use that as well. You can find that here Buyer Management
