I cannot apply for restoration, as the 2nd co-owner under the will...?

According to the Civil Code of Ukraine, in order to accept the inheritance or refuse it, it is necessary to contact a notary and write a corresponding statement within six months after the opening of the inheritance. If the second co-owner, who does not live in Ukraine, but lives in the Russian Federation, does not write a statement about accepting the inheritance, it will mean that he has automatically refused.

In addition, in connection with the aggression of the state in which your relative currently lives, I think that the notary will not have any problems or additional questions.