Marriage cancel after engagement(Ring/Roka Ceremoney)

Sir, My son's arranged marriage was fixed and godh bharai cum ring ceremony was done. wedding date was finalised for after 6 months.however post godh bharai and ring ceremony function, my son realised he did not have understanding & compatibility with girl. She kept fighting with him all the time. then my son stopped attending her calls since about 1 month because he got fed up with her petty fights,ego and arrogance.We tried to sort things out between them but without any successs.Now we want to cancel the wedding because of complete refusal of boy and girl to go ahead (girl also told my son on one call that she was being pressurised to marry by her mother and was not interested to marry herself, after which my son immediately stopped attending her calls because he did not believe in forced marriages).We are willing to compensate expenses of roka ceremony but girls side pressuring us for marriage and putting false allegations on us i.e.- give son Salary proof, address , company name etc.They are threatening to charge us with dowry and saying that the girl is ready to get married when infact the boy and girl have not even been in touch since more than a month. if boy and girl were interested, they would not have stopped talking atleast. the girl's side has also asked one relative to testify that we were demanding dowry and are hence cancelling the wedding and that i forced my son to stop talking to the girl.We want to settle peacefully and want our jewellery back but girl's side are goons and are threatening us with dowry charge and fraud charges if we dont marry the children. they are questioning my son's qualifications and want to see his documents but now since we dont trust them anymore, i dont want to show my son's documents. My son is working in USA and hardly talked with girl for 20 mins before Roka. Girl's parents pressurized us for the godh bharai cum ring ceremony immediately after the roka and got it done within 3-4 days of roka after which he flew back to the usa. Please suggest the legal implication on us. Regards