Ha ha, you gave up a great opportunity to preserve the mystique of your superior bean knowledge there

We're all just googlers ultimately...
I am of the opinion that keeping knowledge to yourself to provide an air of mystique and superiority ultimately is detrimental to the general quest for knowledge. Learning correctly about the world is hard enough without egos making it harder.
I did receive some kidney-shaped, mottle-shaded beans in my packet of Bantu too. I didn't bother growing them out, cuz what I really wanted was all those beautiful little multicoloured jelly beans. Still, there's something that feels really authentic about the variability -- somewhere in the world, these are people's normal cooking beans and they don't make a fuss about it. I like the idea of ones that "fell into the pile and went along for the ride".
Something like 90% of the interesting seeds I have probably came around that way. In fact, besides Owl's Eye, off the top of my head the only other two cases were the seed I ended up growing and saving was the dominant seed in the bag (or at least, reasonably common). are the Indian Sky-Pointer cowpea (a small red cowpea whose pods have the odd trait of having extreme negative geotropism, so they grow pointing straight up!) and the Thai/Vietnamese greenheart cowpea (black skinned green cotyledons).
Pretty much everything else was a rare one or two seed inclusion, Sugarpod (speckled cowpea with very sweet tasting pods, am working on developing it into a snap). Coals In The Candle (black eyed on black cowpea with dead white waxy pods, but it has reverted to green for the moment, so it needs more breeding), Little Workhorse (another cowpea, and very productive. Though to be fair the only different about it versus the normal beans in it's bag is the Little Workhorse has mottled seeds, not plain). ALL my non red azuki beans and rice beans (though I have since learned that, if you go outside of China, non red rice beans are not all that uncommon.) The mottled English pea I use (it's super tiny but also super fast, so it can actually make it in our rather short spring.). And of course, all of the wild and weedy seeds as well.
Oh! I got some steel blue ones from my harvest; can't remember if I planted any that looked like that. They also have a copper dot on them, I think on the 'back' opposite the eye. There are very few, but I'm willing to send some your way at the end of this growing season!
Doesn't really surprise me. Based on it's appearance I believe that Fort Portal Jade is just the result of someone picking green seeded beans out of the Bantu population and letting them grow amongst themselves. So any color that showed up there should show up in Bantu.)