Not a Gen 2 cable; I've got a fair number of those lying about and they appear interchangeable between the Mega Jet, Genesis 2 and 3 (to name some systems I found also lying around).

Game Axe sounds plausible. I can't imagine any "modern" system getting by with that few pins really - the Genesis 2 cable and connector have maybe 8-9 pins inside the shield (which takes a similar shape), need ground and other signals.