I didn't comment on the dash cam thing, as I know recording people while working is a no-no in my state. Though the idea of letting a mechanic replace, or remove items that were not requested and not being notified about it is shady. Like I said earlier, new parts do fail, and dealers can make mistakes - it isn't the norm, but there are reasons why lemon laws and 12/12 dealer parts/labor warranties exist. I wouldn't go back to a shop that would remove/replace parts and not mention it personally, but that's my opinion.
I would agree though that they should speak with them and see about a revised service transcript calmly, before ranting and raving about recordings. As others have stated, they could make a comment about noticing newer looking parts - or hey, the finish is scraped on these screws - what have you. They don't have to go in heavy handed.