My question involves a traffic accident in the State of: Texas

My husband was in an auto accident and taken by ambulance to the hospital. The city had my car towed to the city auto pound. Subsequently, the tow truck backed my car into a trailer hitch of a truck already parked at the pound. The hitch went completely through the back bumper and made a large hole. We spoke with a supervisor about the damage and she said we will have to go through the tow service and gave is their information. The car sat connected to the truck's hitch for several days, and the insurance adjuster went to the pound to estimate damage from the actual wreck and noticed the damage to the rear and took very good pictures. A few days later, I called the wrecker service to get insurance information to file directly so I didn't have to pay another deductible; however, the guy was a complete jerk, cursed me out, and hung up. I told my claims respresentative about what had happened and he called to speak with him. He acted the same ways towards him and refused to give him any insurance information or pay for the damages. I have called the city auto pound, they will not give me any information. What can I do to get this tow service or the city to pay for the damages to my car? Who is actually liable since the tow service was hired by the city and working on behalf of them at the time? Any information would be appreciated.