The main reason Layton was able to hear the broadcast was because he was connected to the plane where one of the ancient entities resided. It was the very plane where he had been sent on a mission from the Wizard World. Layton wasn't exactly sure how this individual who wanted to imitate Pangu had found the coordinates of that plane, but since the coordinates were already revealed, there was nothing else he could do about it. He wasn't perfectly in tune with his avatar in that plane for reasons of secrecy and safety, but soon enough this would change. He was actually looking forward to the shift in perspective and the new, strange laws he would glean from the experience.
Not wanting to take the opportunity alone, Layton sent a message to Zero and Lilith. Although they weren't in close proximity with each other, their previous relationships and close contact meant they possessed a causal connection strong enough to transmit information through the vast void.
