My office desktop recently upgraded from 1803 to 1809 and all the user files (documents and media files) DISAPPEARED irreversibly. Clearly Microsoft didn't fix that problem when it surfaced in 2018. Shame on Microsoft!
All I can say here is, "a fool and his data are soon parted company". This being a work computer, try not to take that too personally..
In all honesty, I have no idea how to use the "library" functions in Windows 7. Any data stored on C:/ has to be viewed as expendable. The only actual files I have stored on any of my C:/ documents folders on any of my machines, are those on the desktop. Everything else, is on physically separate drives. "Pictures, Documents, Videos, Music", anything that the Windows "library" function manages, are all on separate HDDs.
With the reputation Windows 10 has developed for screwing up computers with its forced updates, in all honesty, if I were using Windows 10 and I knew I was doomed to accepting a version update, I would go to the extent of unplugging all the drives in the system, (save for C:/, of course), before I ever allowed the update to continue.
And you can tell your boss, "captaincranky said to tell you, I need more drives in my machine".