I just noticed a similar observation here. (Now I’ve created a circular reference ! 
)
This is not a problem on the Win version. When a pair of {image+sidecar} files are renamed from outside PL, there is no need to update the filename within the sidecar file … PL does an auto-repair the next time it encounters this combo.
@StevenL: Just in case you’re monitoring this discussion; Please do NOT “fix” this situation on the Win version (to have it behave the same as Mac) - as it’s extremely valuable being able to rename {image+sidecar} files from outside PL - with full confidence that PL handles this elegantly.
John M