Evidence can be sent to a mediator, but as stated, our evidence is 100% watertight.
Why not post all proofs or evidence on here? With that, we all can know exactly why you can so sure if OP has multiple accounts and abused your bonus.
Yap, post here all evidence, screenshots which can prove that OP with his alt accounts coming from the same IP address and finish this drama. It's enough proof if you already have a one person, one account rule. Usually, cheaters create more accounts just if there is a bonus.
I know some casinos when they catch the cheaters, give them back his deposit and allow them to withdraw it. So no one is at a loss, especially if we talking about small amount like 30mBTC.