"Dreaming of jumping through the void specifically?" Alice asks. After all, it could be that the other meant dreaming of the void in general.. which happened to all of them at this point, hasn't it.

Which is why Alice figures that it's probably the more specific version the girl is indeed referring to.

"Did you like it in the dream?"

Maybe it didn't have those dumb nauseating effects in there, if it's a dream. Then Alice imagines it might not be so bad. Probably boring, though, after moving through a long stretch of nothingness.