Payment for less than half the quotation for damages - ********* company

A client of quest claims knocked into my car on the 26 February, not my fault at all. He was driving the wrong, reversed, clutch slipped and hit my car. Quest claims now mention that I was partly negligent since I did not see him. How is that even possible, he hit me not the other way around and admitted it was his fault. This company will look for every excuse to not pay the full amount for damages, The client is a young inexperienced driver who hit my car! The damages is R 65000 and to my horror quest claims came back reducing the amount to R 25 000. How did the assessor get to a quote which is half what a professional repair shop will charge. Old Mutual will lose alot of potential clients due to the *****ery of this company. My car is also warranty and the assesor says its not , and reduced a professional Mercedes approved quote into half for parts etc . If there was an ombudsman that deals with 3rd party claims, please let me know.