Rupert has seen flickers of alert and wariness appear on Zen's expression several times, especially when Efran started to guide them in their initial descent into a subway, but he either pushed any questions he had aside or figured them out for himself.
He never did tell enough details about how this whole thing would go down. That's why he made a note to answer any questions he had when they were all settled later on - as well as tell him more about Efran and his history with him.
They followed Efran through what seemed to be a security checkpoint. He really played his part well in keeping the surroundings clear, and there was never any trouble on their way. It was a seamless path to tread, which only further proved that a human shelter was hiding around this area.
