What

My younger brother's wife has left the house for attending her sister's marriage an year back. Its almost 9 months that the marriage is done but she is not going back to him stating stupid excuses. My brother is leaving with our parents in Kerala & he is into a private job. The girl wants him to leave our parents & leave with her at her home. It is five years that they have been married & they have a baby girl of 2 years. My brother was very attached to his daughter & was ready to do all compromises other than leaving our parents. There's was a love marriage done as per Hindu rituals. We were told by the girl that she is Hindu & her parents died when she was very young leaving back a younger brother & an elder sister. Now we have come to know that the girl is Muslim by birth & has got two elder brothers also & one more elder sister. We were not aware of this fact & are feeling cheated now. We had also approached SSP office & were directed to Parivar Paramarsh Kendra. My brother appeared twice at PPK but the girl did not attend the counselling. Now what is the best suggested remedy for us? Should we file a case in section 9 of Hindu Marriage Act or go in for section 11 & 12 of Hindu Marrige Act? Or we should file an FIR for 420? My brother do not want to leave his daughter & at the same time do not want to continue with the girl neither the girl is willing the same. We also know that the girl will not be able to take proper care of the daughter as they leave in a very miserable state. We are very confused. Kindly suggest.