About family reunification

Good day everyone. Could someone pls give me some ideas on how can we deal with my fiancees matter in regards with his x wife marriage. Soon i will be applying for family reunification for spouse , then one of the requirement is our merriage certificate , and if divorce his divorce paper from the country where the marriage is held unto.. The thing is his marriage was in philippines last 2005 , and he divorce with his with wife last 2012 that was 7 years ago in norway , in norway the marriage is legally disolve but in philippines they are still married. His x wife now is already a norwegian citizen , both of them are non filipino nationals. Do you have any idea of the process that he cab do for his marriage here in philippines be legally annulled , and how long will it takes ? Like how many months or years. Thank you and Godbless