My wager: this is a permissions issue rather than an error. I've seen this many times over the years when one user has limited permissions so they are unable to see versions. Look closely at the where used on yours again and notice the coworker also doesn't show DS0064.slddrw v1/7 but yours does.
The first place I begin my forensics in situations like this is in the group permissions. Specifically looking for differences between the groups the coworker is in and the groups you are in. I like to use excel to compare these side by side. Next is to make sure both users have matching permissions in the folders where the files are.
Also, when you post back, add the "Found In" column back into your where used tab, then take a new screenshot of your where used tab.
Well, you were exactly correct. When we migrated to EPDM we went through a folder "DataLoadStaging". My coworker didn't have permissions to view this folder and apparently that affected files which were subsequently moved to their proper place. Thanks!