mechanic takes my car for a joy ride with his mates

Put my range rover into a local land rover dealership for service and a few other minor issues on tuesday this week and if ready, to pick up thursday. Gave authorisation for the car to be taken on test drive to help the technician diagnose any issues. When i collected the car, i had a look over it and found everything that was on the back seat was in the boot. I thought it was odd a i couldnt think why this would have been done as there is nothing in the back seat area that would hinder any service or anything as there is nothing there to do with the car's performance.
Driving to work the following morning, my dash cam's memory became full which again i thought was odd as i formatted the disc before i took the car in. Curious, i viewed the dash cam and the mechanic, had taken my car home, picked up his girlfriend, picked up his mates and had an evening out with my car, getting involved with a possible fight in Brixton and caused a fight outside a hospital, both incidents all in front of the car and on camera. What was risky is that both fights could have ended up on the car causing damage. He parked up at 1230 at night in a back street in Brixton with some £4000 worth of tools inside the car. I left the tools in the car as i was assured when asked that the car is locked securely under 24 hour surveillance.
I have contacted the garage who have already sacked the tech, and have been very apologetic. The senior director has called me to say that it will be investigated and they await my dash cam footage. They have also offered to refund me in full, nearly £3000 that i have paid so far for the work done on the car.
I'm not greedy so i am fairly satisfied with the outcome but what about the tech who took my car and abused my car and trust. He used all back streets as short cuts and every street was full of speed humps and all were driven over at speed. Should i report him to the police. Should i do anything else or claim for anything else?
what would you do?