If you look closely at the PCB (picture 5) you can see six of the spots have two holes on the left and right. F12, Esc, and the Tilde keys are the others I saw. You can get Skyloong plug-in knobs for about $10. Not sure if those require activation via the software or if they are plug and play.
Bit of a stab in the dark but judging by the photos this is modular. So all the spots that in one photo have rotary dials have keys in another. Perhaps the kit includes 6 but the photos only show some of the possible configurations?