No, that's called coicidence or that's someone thinking they dreamed something. Freud had a whole theory on the meaning of dreams: it's only when you actually start thinking about the dreams that you actually solidify what happened so any myriad of things could effect what you think happened in your dreams
You still have this written:
"As Seth listened, he thought of other things he had seen in his sleep the night past. Something about evil adepts and corrupting the lighthouses. "
That's impossible. Mercury Adepts wouldn't have visions, only Jupiter Adepts have that potential and even then, no one knows!