According to Robinson William's arrangement, the Awakeners who had obtained the Pupil Skill, one by one, entered the cockpit in order.
After entering the cockpit, they used the Pupil Skill as Robinson William had instructed, to observe the scenery ahead.
Not only Zachary, but no one else in the cockpit spoke either. After the Awakeners used the Pupil Skill, if they saw something different, they would, following Robinson William's instructions, record in detail what they saw on white paper.
As each Awakener left the cockpit, Robinson William looked at the text recorded on the white papers collected from them. All five Awakeners who used the Pupil Skill had seen things that were invisible to the naked eye.
Three of the Awakeners specifically saw the mirror surface mentioned by Zachary, one Awakener only vaguely made out something, but it wasn't clear.