I can't recall the last time I seen a stake representative respond to a complaint. I'm not 100% sure but I think they prefer to handle things within their own support system/forum or through an official mediator like CG.
OP have you tried posting in their announcement thread and seeing if someone responds there?
True, this forum is not the right place to actively seek help in a matter like this. Casinoguru or askgamblers would promise more success I think. Also, I doubt stake is investigating accounts without a solid reason. They are the market leader and 6500$ are peanuts for them. That being said, I believe there might be more to the story, but of course I can be wrong.