Probably not the worst deal to miss. I bought the last one and received it today and it appears to be DOA. Can't see it in BIOS, Linux (dmesg), Windows (diskmgmt.msc) or via a USB to SATA adapter. Tried multiple PCs and even taped the 3.3V pin for giggles. Nothing.
The drive I received doesn't match the serial number of the auction/CrystalDisk Info screenshots, so I contacted the seller about a return/refund.
Did you test the Drive also via an HBA such as LSI 9211-8i ?
Did you try e.g. the "Crucial Power Reset Trick" ? That was originally for Crucial Consumer SSDs, not sure if it's also applicable to Micron SSDs. Maybe they do, since they share same Flash Memory Manufacturer and likely similar Controller.
About the Serial Number, to be fair, there appears to be 2 CrystalDiskMark Screenshots, both for the same Serial Number Device (Page 1 & Page 2 basically).
Granted he could have taken a couple other Screenshots and forgot/decided to not upload them for whatever Reason (that would have brought the total to 6, unless he included the Picture of the Device with the other SSD).
I find it a bit weird to believe that you got scammed, given that the Seller has a 100% Review Rating. Sure there are probably Ways they can suppress bad Reviews by contacting eBay Customer Service and use whatever Excuse they can find, but it's probably some Mistake or he forgot to test it (maybe it was already packed and didn't wanted to unpack+repack etc).