Windows Server 2019 - Cannot see MOV files

On our network the contents of the public shared drive is accessible to anyone properly authenticated. There are hundreds of folders and thousands of files. This drive "S" is used heavily daily.

Twice in as many weeks I've had PC users (Win10) tell me that content was placed in a specific folder on "S" for them and that they were unable to see it.

Mac users being Mac, the impression was that they didn't copy the folder/files to the network drive. Today, that impression changed.
A Mac user copied media files onto "S", perhaps 6GB of Mov files. The Media director (PC) could not see the files while other Mac users could.

After checking for hidden files and then checking folder permissions I asked a Mac user to copy the folder containing the Mov files to my USB drive. At the Media directors desk using my USB drive the files could be seen. Further, copying those files to the actual Media mapped drive (restricted to media dept only) allowed the files to be seen.

Still from the Media Directors desk and then my own those files could not and still cannot be seen in the public drive "S".
Logged in as the network administrator there is nothing special about that folder, which inherited its permission from its parent. As Administrator I specifically added permissions for the media director and myself but the files could not be seen. Returning to a Mac user's desk, the files could be seen.

The public drive is wide open for anyone's use and for file sharing where confidentiality is not required. Ruling out operator error, hidden files, and directory level access permissions I've run out of ideas on how to approach this. Even corrupted file should be seen.