"It’s as though there were some sort of field that provided an energy inherent to space itself, causing the Universe to inflate"

Or, inflation was the moment at which our universe - broken off from the outside one, formed its own dimensionality - in effect changing state to create its own Planck scale and its own "energy" and its own "information" content starting point. After all, there is no reason why - that we know of - that it would have to remain causally connected in any way to the universe from which ours was spawned. As we like to say, "The laws of physics break down" - we don't actually know if energy or information are conserved in the transition to a black hole, inside the black hole.