Summer tire change – now bumper broken

Hello, I need help on the following case: I brought my car to our local car workshop for the summer tyre change on Friday morning. Unfortunately, my car came back on Friday evening with a fat bumper accident. The owner of the workshop told me that his employee would have driven against it with another car. He apologized and wants to get the car back on Wednesday to repair the damage. Can I for the time of the repair, or also Nu Is he still driving, just looks shy and everyone thinks I was… No matter how, do I have to tell the workshop or where do I have to apply for this? Unfortunately, I don’t have any experience with something like this, just want to know what is due to me. Thank you very much.