the problem is, while we cannot show that consciousness exists in anything besides ourselves; we KNOW it at least exists inside ourselves

No, we don't. You possess a conviction that you have 'consciousness'. Conviction is not the same thing as knowledge.

That conviction is so strong, though, that even high-powered minds can completely fail to perceive the obvious flaws in their own arguments. Roger Penrose is a polymath, a true genius. But The Emperor's New Mind is trite nonsense. I'm sure Chalmers has a first-rate mind, but he is unable to perceive that his definition of 'consciousness' does not permit it to take part of existence in any fashion. Their errors have more elaborate protections against self-evaluation and elimination than lesser minds might produce, but the errors themselves are elementary.

It's always easiest to fool yourself, and the very smartest people have a hard time finding people capable of seeing through the arguments they make when they fall into delusion, not to mention suppressing their egos long enough to listen to those people.