Can they sue me after their vehicles have been fixed and already been paid through by insurance?

Person in front of me hit person in front of him. The middle car (person in front of me) is claiming that I was the cause of the accident yet there is no damage on the back of his car and minor damage on the front of my car (from a previous accident). The middle car had severe damage on the front his car and the front car has severe damage to the rear of the car. No cops were called at the time of the incident and were contacted in another town. No police ever showed up and I never gave insurance to the person in the middle or the front car. Days later insurance agents were contacting me and I gave statements saying that I was not involved in the accidents that occurred and the pictures that the two other cars provided proved so. The insurance companies dropped claims on me and I am worried that the middle car will sue for any reason.