Annulment case (Section 12, HMA)

Hello Sir, My friend got married through matrimonial sites last year on December 23. Just after 3 days of marriage his wife started quarreling and abusing him and his 74-year-old mother. She asked him to send your mother to some other place I don't want your mother in this house. My friend and his mother were in shock and things were getting worse day by day. My friend tried to speak to her parents but they also took their daughter's side and threatened My friend that if he or his mother spoke anything more then we would file a false FIR against you and your old mother and ensure both of you are behind bars. She was making false allegations against my friend and his old mother and was telling lies to her family and friends. Later my friend found out that she is having mental illness and has been getting treatment from various mental hospitals. After knowing this we realized that we had been cheated by her and her parents by not disclosing her mental illness. They concealed the facts related to her mental illness from my friend and his family and took consent for marriage. We tried to speak to the wife's parents about this cheating and the mental illness of their daughter but as expected they again started threatening. They called their daughter back to their home. We consulted the lawyers and finally sent a legal notice to the wife that we don't want to continue this marriage as you concealed the facts about your mental illness etc. They did not reply to our notice and filed complaint 498a etc. in her hometown. After that, our lawyer filed the annulment case under section 12 (concealing the facts). From his wife's side till.now 125crpc. DV and section 24 cases have been filed. In DV case she has demanded 25 lac+ 5 lacs and 75000 per month maintenance. We have sufficient evidence of her cruelty to my friend and mother. Her before-marriage and after-marriage mental hospital documents etc. She didn't appear In 1st and 2nd hearing of our section 12 case in 3rd hearing she appeared ND filed section 24 (HMA). We understood that the wife and his parent intended to extract money from my friend which is the reason they didn't disclose mental illness. Earlier our lawyer was telling me that we would get this marriage annulled and get the annulment decree as we have the solid proofs and pieces of evidence of the fraud committed by the girl and her parents. I need your guidance, my questions; Q1. Have we taken the right steps to come out of this marriage ?? Q2. what other steps do we need to take against false DV, CRPC125 & section 24 cases to avoid maintenance, etc. in all cases false facts have been given by girl side. Q3. It has been more than since the 498a FIR was filed by police but till now charge sheet has not been filed by the IO, what should we do at this stage? Q.4 Please suggest any countercases that we can file from our side to put pressure on the other party. Thannk you