Adoption of stepchild with complicated parentage

Hello Sir, I have married an old friend (let's call her NB) who has a child from a previous live in relationship. It was an abusive relationship which she got out of to protect her child. The biological father (let's call him AB) was an alcoholic and serial abuser. He has been married to someone else and has a daughter since before living in with NB. He never sought divorce from his first wife, and never gave any recognition, legal or social to NB. NB got out of the relationship while pregnant. During her pregnancy, she found help and support from a colleague (let's call him AR), who wanted to marry her. He insisted on giving his name in the birth certificate of the child when he was born. Unfortunately, the guy turned out to be a fraud, who is married and has a son. NB was traumatised along with her ailing parents due to this betrayal. This was 15 months ago. The child is now 18 months old. Now I have married NB and want to adopt the child. AB, though the biological father, is not in the birth certificate. AR, while not the biological father, is in the birth certificate. As per adoption rules in India, I would need consent from the biological father. AB has refused to sign any legal document that gives any recognition to the child, since that would land him in legal trouble with his first wife, but he continues to harass both of us. AR has agreed to provide NOC in case of adoption. Do I need consent from both AB and AR, or just AB or just AR?