Accident with UPS equipment. What should I do?

This accident happened when I was properly parked and positioned in a marked parking stall at the local mall. While in the mall a UPS delivery truck driver parked his truck behind me in the center of the aisle blocking 3 to 4 vehicles. I waited for the driver to return, he returned and thanked my for waiting. The UPS driver then pulled his truck away giving me the opportunity to back up. I backed between 2-3 feet and heard/felt a loud/strong impact to the vehicle. I stopped and got out of the vehicle to find the UPS driver had pulled away leaving behind what he later called his "rollers". (A metal device approx. 4 feet long, 2 feet wide and 6-8 inches high used as a type of conveyor system to load and unload his delivery truck. The UPS driver also heard the sound of the impact and stopped. He heard the bang over his very loud Dewalt brand portable radio setting on the dashboard. He walked back and stated "I totally forgot...I am sorry...I am a new driver...I have to call my supervisor." When my vehicle hit these "rollers" that were laying directly behind my vehicle flat on the ground the device flipped up and contacted the rear bumper at the passenger side of the bumper causing the bumper to come loose from the vehicle and hang away from the vehicle about 6-8 inches with scratch and scuff marks on bumper. The driver stated that he had deliveries to make and left but his supervisor would be there shortly. The driver gave his name and employee number before leaving. Approx. 30-40 minutes later the supervisor arrived. The supervisor took photos, provided his business card, and stated that the driver should have not driven away leaving his equipment behind and stated that "these accidents do happen and our insurance company Liberty Mutual will pay for all of the damages under the general liability policy so don't worry your insurance will not be involved". The UPS supervisor took my name, number and vehicle plate number and stated Liberty Mutual will contact me within 24 hours. My vehicle was driven home .7 tenths of a mile under 30 MPH with the rear bumper banging in the wind. I am left with a vehicle not safe to drive and still have not heard from UPS or their insurance. I work full time and I am without a safe functioning vehicle. This accident occurred Monday June 7, 2010 at approx. 5:35 pm in Huntington Beach, CA. My vehicle is a 2007 Toyota Camry fully insured, paid off with no prior damage. There were no injuries. What should I do to get transportation to work and protect my rights?