Money fraud

My mother was a member in a kameti (not authorized), around 50k was due when the lady ran away with the money leaving her husband and daughter. Her husband claims that he is not aware of the location but she still owns 2 house in our locality where her husband is residing currently. Her truecaller shows that she and her son constantly talk to people over call despite that her husband claims that he has filed a police report and they are unable to track her. what should we do to get our money back. The lady still resides in delhi and the whole cause of action took place in Delhi itself. Also, her husband claims that she took away the kameti diary along with her.