What is the State of California law prohibiting relatives from issuing divorce certificates for their diseased?

An out-of-country woman is trying to get her diseased son's divorce certificate from California, but was told that the California law prohibits issuance of divorce certificates for anyone other than the beneficiaries themselves, to protect the personal lives of celebrities as she was told. And since her son is dead, and since his late wife has an interest to deny the divorce for inheritance purposes, the mother does not know what to do. Can anyone name the law or order stipulating such. An online reference to the code would be very welcome. Thanks.