You were supposed to do your own research. Bittrex's terms were completed.
If an exchange is holding an ICO for a scammer..it's their fault. Once Fincen kicks in..it'll all be taken care of. Regulation is another thing that would help keep people away from scammers like these.
it wasn't a scam until btc was sent, how could bittrex have known it was a scam. if those that knew it was a scam why invest in the ico
the only blame you can put is on the dev