4 wheeler accident and opposite person sent legal notice

Hi Team, I was working with a private company and was using my official car.The following accident happened on oct 2016. I was returning back to my home with my family after having our dinner in a hotel around 9.30 pm to 10 pm (Approx) , at that time i was trying to take a U turn , Since the place where i took a U turn is very close to the hotel , i was driving very slowly,and i switched on my right indicator , i looked the right mirror and i turned the vehicle , at that time there was a sudden sound, i thought that i had hit a road divider so i stopped the vehicle to see what happened, then i realized that the car was hit by a bike with rash speed which damaged the car front & rear doors & window glass got broken ,the door got completely pressed inward and was not able to open. Seeing the bikers ,Immediately i parked the vehicle aside and stopped a mini tempo, took this 2 persons to nearby hospital and i requested the hospital persons to do medical assistance. Then again i came back to the accident spot. In the accident spot, there was a traffic police, he asked me to take the vehicle to nearby Traffic police station, so i took the accident car to the traffic police around 11.30pm (Approx) . There they asked to take the vehicle to RTO inspector for inspection. Meanwhile i contacted the hospital,to check the health condition of the 2 person, they said 1 person was admitted & he was given trips with medical assistance & he is normal and the other person left the hospital after getting the medical assistance. Later i took the vehicle to RTO inspector and received the RTO inspector report. Meanwhile i left the company and joined in a new company. In 2017 Sep, these 2 persons have sent a legal notice to my previous company and insurance company. Now i am requesting my previous company to give balance dues and service letter but the company HR is denying and saying that i have to sign a indemnity bond with them. Kindly clarify me whether i have to sign that and legally its required. Whether i can send a legal notice against my previous company.