The FileManager component makes the assumption that all files and directories can be uniquely adressed by name and path.
Unfortunately, this isn't true in many cases: identifying a specific file could require additional information (like database record ID or namespace) that cannot be provided globally for the page and therefore needs to be stored individually with each file entry inside the client's datamodel.
(In my case, different entities in the database have their own "virtual storage" where files are references as items stored in a cloud block storage service. This means that I can several files with the same name and path (but diffreent content) referenced in the database or even several files with the same name and folder linked to the same entity).
After trying to use a richer object in the JSON returned to the FileManager Read action, I have come to the conclusiong (confirmed by support), that doing so will break the compnent (rename will not trigger any action on the server, update will cause a JS error inside the kendo libraries).