Not to be a skeptic, but I hardly doubt Viou scammed you...
I would be willing to bet cash that you added/were added by an impostor that used Viou's name. Always double check e-mails to make sure that its not an impostor, and ALWAYS request PM's!
Sorry to hear you got scammed though. The only thing you can really do is fill out a scam report and provide all the information you have of the transaction and get the fucker banned (if he even has as Sythe account).