Spill the beans , if you are 100% that they did something stupid. Lets see if somehow it can be fixed.
Naming isnt an issue if they genuinely made a mistake.
I recall on my first build , mechanic forgot to torque down and add some loctite of the oil pump gear.
Lucky i was warming the engine in the garage when all of a sudden i could hear a scraping sound.
Stopped the engine gave them a call and they came over. Took the cam cover off and there it was at an angle. To say he was red faced was an understatement.
Needless to say i havent used them for my SC engine build and will never ever use them again.
This is a mistake not total negligence but if something went wrong they would of paid for the repairs