You guessed correctly!
In the fin/fin screws/footstrap/footstrap screws/brass extended mast base nut that came with the board when it was new there was a loop of nylon webbing (kinda fuzed together at the screw holes) that fits the 2 hole pattern in the bottom of your Kombat 114.
The concept (and it works rather well) is to tie a weighted tether to the loop after you install the 2 screws.
Set the weight just above the sea bed under the board, and you will not get the tether line wrapped up in the center and rear fin.
All the other places you could attach a tether would influence the new sailor's directional
Attaching it in front of the center fin just makes sense as the new sailor does not even know he/she is on a tether until the end of the rope, or when the instructor takes up the slack.
If you decide you want to use it, get some short 6mm x 1.0 footstrap screws.
Regular footstrap screws, or the 7mm later footstrap screws will punch out the back of the small double insert that's molded into the hull.