I'm a little confused as I was reading on the Helix site linked many people say it was a rom hack in the comments. And the Helix admin even comments on it.
Going by the assumption that even an inkling of this is legitimate:From what I can tell from those comments, the content itself is legitimate, but the Helix site showed them in a stream of a ROM hack (along with some fan content to make it go more smoothly or whatever), and poorly disclosed that fact.
Boy, this is an absolute treasure trove of information. It really shines a light on the infancy of this series, how Capsule Monsters may have worked, and gives us an inside look at the process of coming up with the monsters in the game.
Also, really helps solidify these as truth, with a handful of Pokemon from the 1997 Spaceworld demo existing in this very early build of Red and Blue.