Future line of actions in this scenario

Hi. I got my sister married through matrimony but issue started after 1 week of marriage he is already contact with another girl before marriage and same continues he is not even concerned about our efforts and just for the sake of satisfying his parents he did this he did all things for forcing my sister out by abusing and getting drunk and even threatened us in calls in midnight so we got our sister back we had given 3 lacs dowry for making mangal sutra in our tradition we have every pics and videos while giving cash but he is showing the receipt of that gold chain in his name and several other household items with 2 rings, 1 gold chain, 4 gms gold coin. we got FIR in local police station with 498A,406.504,506 with these sections but after issuing 4 notice he didnt came to police station neither his family in last notice police submitted personally notice with constable he and his family created ruckus and told they will commit suicide n all moreover he had written IO name in notice by saying that IO is torturing/threatening and signed below we want divorce and our Things back IS DV we need to file now or Divorce Pls advise .....