So what I expect happened is that they did a low level format and put it back in service. Because they don't track at the component level they don't know what machine it went to.
I expect this is coming out because "shredded" drives are probably handled by an outside company that WOULD keep track of serial numbers and would provide certification, by serial numbers, of destroyed drives.
If this was a Dell computer their automated manufacturing “build” sheet for her s/n ‘puter would have the s/n’s of the hdd recorded .... if the drive was reformatted , put in a “spare” status and re-used in another computer then the data is lost. If it was simply quick formatted and is on a shelf then the story changes .. but I think we all know it’ll never be produced and no definitive tracking of it will ever be established.
In my experience with PC’s an IT department will keep spare computers for swapout , loaded with whatever apps the organization uses and the tech would only load special apps that aren’t in their standard configuration. Unless it’s an easy to diagnose and fix minor issue like maybe bad memory or a network card the user usually gets a “new” computer.