That's a 3rd party wallet you should never enter your private key or seed in any unknown wallet/tool UNLESS you have removed all bitcoin first that is the first rule of claiming any fork
The only real issue was the official pool started mining on a different chain somehow probably something to do with the premine and they made good my crediting the accounts from their own pocket everything else is running good
I have same problem
I SCAMED WITH THE BTG NETWORK
I downloaded BTG wallet from the official site (https://bitcoingold.org/downloads/) and have claimed my BTG's with "privkey". Then my BTG coins showed in my wallet. But after few hours they get stolen! from network or from the developers. , my "privkey" is only entered on developer wallet. I want developers to restore my 58.03385070 BTG !