Flashing Folder and Strange Partitions

I'm trying to help a colleague fix his computer, he discovered the flashing folder yesterday and we are in Brazzaville, Congo, where there is no certified Apple help.

First I tried holding down Opt+R during startup, and continued to get the flashing folder

Then I tried holding down shift, and continued to get the flashing folder

Then I held down option, and got an option for internet recovery. You don't want to know how many hours it took to access on Congolese internet

I opted for Disk Utility, and I saw the drive listed with a single volume, OS X Base System. But the capacity seemed diminished -- it was listed as having only 1.33GB capacity and 40,752 files constituting 1.3GB (only 31.3MB available)

I had the option to click "verify disk" which I did, and was told that it appears to be OK, and the File System check exit code was 0.

Yet, when I tried to select a drive to boot from, there were literally no options. When I tried to reinstall OS X to a drive, it also gave me literally no options. [usually there is an icon or a list to select from, and that area of the screen was literally blank]

Disk Utility also had greyed out a lot of the standard First Aid options. So instead I went to Terminal.

My diskutil list yielded 13 disks, ranging from 524.3KB to 6.3MB, all untitled. The first disk, disk0, had two volumes, a 30.7KB Apple_Partition_Map and a second, Apple HFS OS X Base System at 1.3GB.

I used verifyVolume and got the same information as I had gotten in Disk Utility (volume appears to be okay) so I tried to diskutil repairvolume disk0s2 and was told that the volume was unable to be unmounted for repair (-69673)

Even when I tried diskutil unmount force disk0s2 it still failed to unmount.

I am obviously in the recovery platform so I don't have access to any other applications or services, and I am wondering whether his hard drive is completely borked (technically speaking).

The things that concern me are that the drive refuses to unmount, and appears to be too small in size, considering his machine is, from the looks of it, a mid-2011 or 12 MacBook Pro.

Please, any advice would be so so appreciated, because I've reached the extent of what can be discovered via the net.