Reply from okpay support

As you know all OKPAY payments are non-reversible according with our Terms of Service:
https://www.okpay.com/en/company/agreements/terms-of-service.html
OKPAY Inc. and MtGox Co Ltd. Companies have a contractual relationship. The decision to reverse the payments can not be done solely by OKPAY without violating our agreements. However we are working on the solution for this situation. As soon as we resolve this in cooperation with MtGox Co Ltd. we will let our clients know.

Thank you for your patience and understanding.