So, I haven't read that paper by Krauss et al. that you suggest, but they and you seem to be saying that the event horizon must have some special local properties, which seems implausible to me. The event horizon is just a perfectly normal region of spacetime which happens to be such that trajectories on one side of the region will never leave its interior. We could already be inside the event horizon of a black hole, and there would be no way to know it. It seems wrong to consider event horizons to be boundaries of the Universe/Reality. Perhaps I am missing something, and I will look into these arguments in more detail at some point. I am very interested in this kind of thing, and in particular questions of discreteness and infinities in physics (but I cannot yet claim to be an expert).