Requirements for Irish Moroccan Marriage

Hello everybody
I'm a Moroccan and im marrying my Muslim Irish fiancee soon , and i've being told from the honorary embassy services in Morocco that she needs to apply for a Certficate of Coutume that we need to complete our marriage file in the court here in Morocco..

The problem is , we dont know where to apply for this Certificate of Coutume , my fiancee lives in London and she was born in London too , but she holds an Irish passport , so now i want to ask...where she should apply for this Certificate ? is it in the Irish Embassy in London or is it that she should send the application to the Irish Embassy in Portugal (Which is acredited to Morocco) ???

Please if anybody here , ever went into an Irish/Moroccan Marriage before , do forward me your answer..thanks so much :)

My Regards :)