Learn the definition of 'scam'. This dev cannot be a scammer by definition. He didn't sell you ICO coins, and didn't dump a premine on you. This is an abandoned project, like many others in crypto. Its pity the dev disappeared and its sad to lose the last exchange - this project was really promising, the idea was great and the community was very good at some point..

Is Bittrex indeed the only exchange for this coin?