Looks like this "GRAV" hardfork snapshot was just a ploy to try to pump up the price of synx before an exit. I advise not giving your private key to anyone until some information is provided which I suspect it never will be.
Synx is a busted company, I got out in the summer. It's only good for day trading - Buy under 3.5k, sell over 4k. Profit every time.