The First Wall was the Phantom's first step towards the K3, but as with all things, it was not a strict rule that all the Two Walls and Phantoms followed.
Everyone's energy, will, abilities, and path were different, and sometimes this could lead to unconventional outcomes despite expectations of something normal, predictable.
It was unknown how much time had passed since Adam's plunge into darkness, but soon he slowly opened his eyes.
He was in his inner space, but it seemed to be something deeper, a forbidden place where Lone Blaze, his Nexus, the artifact, or the Vault could not go.
Adam didn't even see his Evolution Tree here, though he sensed its presence, it seemed that the Evolution Tree didn't want to show itself early.
The only object that was in front of Adam was the Two Walls, both at once since their progress was linked, especially in Adam's case.