After major service - engine badly damaged

On the 2nd of October, I took my vehicle, Renault Grand Senic for a major service to German Auto Care Specialists in Pretoria Gardens. Prior to the service we discuss the major service. The cost will be R895-00. At about 14H30 I went to fetched my vehicle, only to find one unknown male worker still busy with the vehicle. I asked him where the owner was, and he informed me that he was not there. I waited about 40 minutes for the owner to arrived. I informed the owner that I was not satisfied with the service, because a major service was not done and he informed me that I get what I had paid for. I asked him why is the computer not been reset after the service, and why is the service book not been stamped? He informed me that he arranged with another guy to come ant reset the computer, but he had not been there yet, and he did not received his service stamped yet, and I must bring back the vehicle the next week and then he will reset and stamped the service book. I left but after about 10 km the car broke down. I towed the car to a Renault specialist and they informed me that the valves bend because the cam belt cover was not put back properly and that cause the brake down<br> <br>