It would need a new WFX plugin function that would - if defined - overrule the existing function.My point is that TC cannot guess if the column definition will contain this kind of ID. TC should anyhow continue to handle internally filename and consider panel with custom columns just as a view that display what the user want !
Another way would be a global flag that defines if the filename is a display name or just an 'invisible' ID. Somehow this way seems to be more elegant to me...