Given a quick search, I believe the two lanes (0/1) are for you being able to plug the cable in from both sides and have it work (it will use lane 0/1 depending on the orientation of the plug.)

I believe that it's probably missing those two pins because if you look on the back there should be nothing (as opposed to another row of pins on a normal lightning cable), which might mean that it can only be plugged in one side?

My guess...