There are three ways to receive a duplicate of the marriage certificate: go personally and receive; or address to a civil records office at the place of residence – the office shall request a duplicate marriage certificate and issue it to you. You will have to present your passport and pay the state duty; or you can authorize a representative in Vladivostok to obtain a duplicate marriage certificate for you (power of attorney is required). You decide which variant is suitable. You shall apply to court in Kaliningrad and give your wife's registered address and actual place of residence.

In case your wife is against divorce the court will to establish a reconciliation term not exceeding 3 months. In case the reconciliation is not reached upon expiration of the mentioned term your marriage will be terminated (Art. 22 part 2 of the Family Code of the Russian Federation). On the assumption of your letter I do not think your wife has any rights to your parents' apartment.