I'm not an organiser and this is not an official answer, but in my experience if the game is hosted on itch with steam keys attached, then the keys don't unlock for people who got the game in a bundle or for free. I've had bundle customers contact me before and ask for a key (maybe twice) but when I've explained that the key isn't available, they've been fine with it.
Hello - sorry for the wait. I can confirm that what Aetheric said is right - the main reason why the page says to avoid Steam keys is that it may not work for people who buy the bundle. As long as your game can be downloaded off itch.io and not primarily on Steam, it's should be fine. That seems to be the case with your submitted game, so it's eligible.
