[quote=@Techspert]
<Snipped quote by Balance>

Technically the layer would still be in the same physical space, but it doesn't really matter.
[/quote]

At that point she can simply move herself out of reach of the simulation. There must be an "out of reach" because there is a separate simulation for Ruby and Soren. If they both occupy the same physical space, then there must be a way to layer it, and therefore Maddie could find "the real world". If they do not occupy the same physical space, then there must be some place that is not covered by both, or she can simply find the reality of someone not in a simulation.

EDIT: In case you're worrying, note that Ruby and Soren can't actually get out the easy way Maddie did. They're not used to losing presence in a Page, and if that were to happen on such a large scale, they would be put through extreme rigours under reconstruction and would most likely be incapacitated for a good while.