I would guess that the person formatted drives on the machine and then simply copied the operating system folders over and renamed them accordingly. They are not the Workbench3.1 disks that came with the 4000T as it would say Workbench3.1 and not System3.0 and pretty sure you would have got the drawer images on the main folders.
OS2 has a black upper section. Workbench 2.0 does show disk icons for OS drawers as they appear here, however.
