Can I use MBS Files.List on FM server on Mac to access network volume?

I'm trying to use MBS to access files on a network volume from script running on FileMaker Server on macOS.

I can mount the volume successfully...
Set Variable [ $MountVolume ; Value: MBS( "Files.Mount"; "smb://" ; ""; “"; “"; "" ; "" ) ]

I can see that the volume is mounted...
Set Variable [ $FileList ; Value: MBS("Files.List"; "/Volumes/") ]

But when I try to get a list of files from the volume, I get an error...
Set Variable [ $FileList ; Value: MBS("Files.List"; "/Volumes/VolumeName/") ]
( [MBS] Failed to read directory: Error 1: Operation not permitted )

I can even unmount the volume successfully...
Set Variable [ $Volume ; Value: MBS( "Files.UnMount"; "/Volumes/VolumeName" ; 1 ) ]

Understanding that this points to a permissions error, I left the volume mounted and ran this command from macOS where the FileMaker Server is running...
sudo -u fmserver ls -l /Volumes/VolumeName/
...The command returns a list of files on the network volume.

Can someone help me determine what I'm doing wrong in this setup or suggest an altertive way to access these files?

FileMaker Server v19.6.3.302 is running on macOS Ventura 13.5.2. The network volume is another Mac also with Ventura.

@ccr Welcome to The Soup !

Permissions error is probably, as you said, the reason why it failed. The scripts run for a user that do not have access to the network volume. I don't recall what the user is, chances are the explanation is in FMS Help file.