Has it occurred to you that this all happen because of the police? The wire was stopped at the bank, not CryptoXchange. The bank is the one that is requiring the documents. And they can't just convert the funds to BTC, because MtGox is on their ass too.
You know this for a fact or you're supposing?
I have a hard time believing the bank would be aware of "stolen bitcoins". Red flags would only be raised on their end if perhaps the account the wire was going to was "marked" somehow.
And if that was the case, I guess CryptoXChange could just say that and relief the burden of his shoulders ("it's the bank, not us! here's proof..").