Marriage annulment and alimony

Hi All, My brother wrote MOU agreement to pay Rs.10 lakhs as permanent alimony. Now court passed annulment decree. As far i know for annulment decree no need to pay alimony. My advocate saying need to pay money as per agreement. Now this agreement valid or not? Can wife demands alimony or maintenance? If maintenance case will file then husband need to attend court to fight against? if absent can court has the power to award alimony or maintenance? Thanks