Umm... so polo has been hacked before, they raised security measures and repaid the users who lost funds. It has been over a year since then and the staff (both behind the scenes and in the TB) have grown significantly.
You would think that with their history and man power, they would have security pretty tight. The only vulnerabilities I see are "user-error" in which some dumb-ass (either mod or user) makes a mistake. Even if an attacker managed to send withdraw requests, the coins are (from what I remember) in cold storage and you need 2fa or email confirm to do a full withdraw.