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. 
The OpenLedger guy is pretty active on Twitter. You can ask him about what do there. I recommend not accusing him of scamming or anything at first as he'll be less inclined to help you.
I sent a message to OpenLedger, using the form here https://openledger.info/contacts/Also I sent email to BitShares using the contact email dbis@bitshares.org, which they provide here: https://bitshares.org/#/
No reply in both cases.
Out of curiosity, what were you planning on buying at Bitshares? I notice its undergoing a pump, but other than that I can't imagine anything new is happening over there.
I wanted to buy BitShares because I think that the future belongs to decentralized platforms. But since the price of BTS was slowly decreasing during long time, I bought only 283 BTS, and left the rest of my money in Open.ETH, thinking that my funds are safe. But it turned out that BitShares team always lies saying that their platform is decentralized. There are serious risks and now I want to warn others.