Car dealership employee took my brand new car and put 239 mile on it while waiting to be fixed.

I took my brand new car into the dealership to be fixed for a check break fluid light. When I left my car at the dealership I took a picture of the odometer. When I picked up my car the odometer was 239 miles over what it was when I dropped it off. The paperwork with the mileage in/out was falsified and said they only drove the car 22 miles. When I confronted the dealership they said that the employee was fired. They had no idea where he went, what he was doing, or if he drove my vehicle in a safe manner. They didnt even tell me that this had happened. They told me there is nothing they can do and that they would give me a free detailing and a free oil change. I cannot accept this as for I do not trust this dealership for their employee basically stole my car. What are my options?