The problem is, as I understand it and someone correct me if I'm wrong, that the instant you acknowledge the brand as Square Enix's, you're essentially shooting yourself on the foot. It's like saying: "Hey, I'm using their brand freely even though I shouldn't do it".
Of course, it's not like you're allowed to do it even if you don't mention it. It's like when you enter the US via plane and they ask if you want to attempt an assassination on the president. Trying (or succeding!) is already a crime. But doing so after saying you would not try and do that is worse because you lied about it, or something to that effect.
Either way, my take on this is that they're using the Final Fantasy name to promote themselves. They'll get the game going, they'll get a C&D letter, they'll make a fuss out of it, accepting it gracefully and they'll change the game to something else with the same mechanics. Voilà!! There's no way in hell they're hoping to get this out and exposing it so early.