That sucks! I had a similar issue with ebay, sold my Vive to a guy who said it "wasn't compatible". I contacted ebay, ebay didn't want to know at all and just refunded his money without me even getting the vive back! Livid, not used ebay since.
Wow, that is horrendous. I'm sorry you had to deal with that, especially not receiving the item back. eBay is all about the buyer and they screw over the business user who generates all their income.