Threshold damaged by workshop

Hello, I had my car lift up with a lift in a workshop because I wanted to write down the serial number of the shock absorbers (because the workshop then ordered it and installed it) When the car was then up I noticed that something was jammed between the sill and the transducer, I thought that some thick foam rubber was part of it against sucking. When the car was down then the workshop man took the thing away and threw it into the other transducer (there it sounded then like a st one or metal.) At first glance I could not see anything from above. when I went around the car today I discovered the following: see photos How big is the damage? Do I have to spat and overpaint myself, or is the threshold completely new due? Because if I have a frontal accident then the impact energy is completely on it in this small spot or? So the stability is not restored by spatling, is it? Is there any other way? he reports or investigations?