Referring to this article:
It tells me the location of the local copy of a SharePoint document that is being edited. I don't think I have any hidden folders but I cannot locate that directory. Here is the problem. A Coworker continually only sees a version of a SharePoint document that is dated 2 months ago. I think it probably because he has a local copy that became "orphaned" or detached from SharePoint and every time he tries to open the newest version on SharePoint he actually only keeps seeing this old version. I want to tell him how to remove it but I can't even find out where it is. Does anybody have suggestions on how to fix this situation? Thanks!
Change where you work on files that you check out from a SharePoint library - Microsoft Support
When you use an Office program to check out a file, you can change the check out location to another location on your hard disk or network, or you can specify that checked-out files are stored on the Web server when you work on them.
support.microsoft.com