This bug is in almost al (recent) version of Vegas, like those published from 2010 - 2023.
The explorer does not utilize the appropriate (generic) Windows (file) API system, which results in a buggy and not trustworthy result.
Renaming, moving and other filehandling (from within the embedded explorer pane) can go wrong, it can go good, it's never sure what the result will be.
Another thing is when refreshing the folder (because somehow it does not adopt to filechanges itself, when the content of the active folder is changed outside Vegas).
Sometimes refreshing does traverse the path up, to the connection between parent(folder) <--> child(folder) <--> siblings (files) are distorted.
Not sure why Vegas utilizes it's own explorer "solution" because the W32 API are there for (bug-)free usage.
Anyhow, demo :
On the left a folder (snd-04) with some files (*.mp3)
Right pane is active, click "refresh / F5" to see any changes inside.
Somehow the right pane is not refreshing (which it should do) and the left pane is refreshing (which it shouldn't do) and it's also traversing up to rootlevel (which it's not even allowed to do).
So now you see a folder ("root") with content (*.mp3) which is not there : the files are not in root, they are in another folder.
Pressing F5 / refresh (while the right pane is selected) again, does combine / link / restore the "parent / child" relationship of both folder and files.