Prevent files to be deleted by other admin user

I want to prevent other admin users to accidentally delete a file using FTP access because they constantly update the hotspot folder. Is there a way to make a file accessible only to a specific admin user like file permissions? For example, I don’t want other admin users to have the power to delete the backup files.

Impossible. If someone is admin, then he has all rights. There is no way to protect files individually.