New rear silencer heavily scratched!

Hi Community! Needed a new rear silencer and had a new one installed today by a (free) master workshop. After I had paid, I just drove from the yard without checking the result. Big make, of course, please no shitstorm, beginner error!!! After I put myself under the car at home, I was very scared: The “new” rear sound damper is heavily scratched and uglyly welded on the pipe. Total perplex I am first to the He said that the free workshop would have tried to remove the paper label – which is completely ok, because the exhaust is getting hot – and the welding seam on the tailpipe is also right. Nevertheless, I would like to ask you for advice: Is it really ok that a rear silencer, which I paid for 220 euros relatively expensive, will be scratched so much in this way??? Can he not (like my old friend) he silencer) rust in a few years due to this unsightly treatment? And is the sweat seam really ok? I’m not a professional, have never really dealt with cars so far – so I ask you many times to write me your honest opinion. Should I complain about the silencer or can I drive around with it for the next 10 years without prbleme? Thank you very much! Best regards Frank