False allegations for domestic voilience

Hi all, We are currently facing a mutual consent for my brother who is married for a year now. This was love marriage and arranged by their parents. The issue is she is giving a false allegations on my brother stating that he is mentally toruchering her. Also they went and gave a complaint in woman police station on the same. During that discussion they wanted mutual consent. So we agreed as we saw how they were making false projection of my brother. The girl's father even went and told that my brother impotency. Infact this girl has been in relationship with my brother for three years before marraige and she was 23 when married'. During this course they were physical. So the allegations on my brother was false. We filed the divorce and hired a lawyer as they were very keen in projecting my brother as physco path I don't trust them anymore. The case is not filled. The petiondraft is ready. The lawyer has madeany communication and said that they have to come for signing but last min they Denis saying they want compensation of marriage. We also said that we were willing to return her furniture items that she brought after marriage. Nothing was demanded from their parents'.. now they are threatening that they will reopen the case at woman station and log a compalint. If we don't agree for compensation amount. Everyday her father came up with new ideas to demand money .. some day he said his daughters mental state is at stake and another day he said he wanted amount that he spent for Marriage. Note: I was not part of this marriage neither the discussion. Please advise how should we proceed there isn't any mistake from our end. The girl was not willing to give marraige life a real meaning.