While I don't think he went out and bought a yacht with your $275
The total quantity of scammed Open.ETH is 6775 (see the screenshot), so 12 millions dollars is enough to buy a yacht. But there are also Open.BTC, Open.DOGE etc. He is very rich, this guy, now.
That's just the circulating supply of OPEN.ETH. There's less than 30 OPEN.ETH for sale on the entire BitShares orderbook.
Also, you didn't mention that Open Ledger closed up shop back in April 2020. You would have had a better chance of getting your money back last year.
Not much you can do if they're not responding, I understand. Maybe just remind everybody what this guy did if you see him trying to build something new in the future.