Sued for accident

An year ago my mom met with an accident , mom's car hit a man and his wife who were on their scooter, it was minor incident at speed of just 10 kmph. Man and wife fall off the sccoter and started creating a chos on road seeing my mom was alone , and tried to arm twist her for money , seeing this a passer by helped my mom and beat the shot of the man , not really hurting him badly. That man filed an FIR for this accident and along with medical reports that showed he just had minor scratches no major injury. To follow up the FIR we paid challan for the accident and assumed the FIR was closed as assured by the hawaldar(which now I am assuming he just ate up the money as we didnt asked for reciepts for anything.) and now an year later he filed a case in court asking for compensation for claming due to that incident he has lost job and is under treatment , which by all statndads is pure bullshit, but as Indian law doestnt work this way , we are being asked to show up incourt. I have no idea what to do being 1000 miles away from my widow mom with no one but just her to bear all this. Please need your guidance on this , what should I do , we have the court hearing on 17th Sepetember.