I just watched the video and as I fell, I saw the path to the Inner Mind near the top of the fall so I guess this was used in both quests.
It is indeed You feel woooooozy. The full panoramic is a trip: www.dropbox.com/s/tr7uzfrkv... As featured in the Fireflex 3000 quest (2:21 into it): www.dropbox.com/s/9n2ycbsen... The Outer Mind in the Gwendolyn Quest just led onto the Inner Mind before returning you to Gwen's chamber.
This is "Woozy" if I'm not mistaken. This happens after you swallow the firefly whistle and input the code. When you leave the Fireflex Room you go through this with a buff called "You're Feeling Woozy". Source: I have two alts that went through this, plus myself.