The shift from Milliways to the air over the ocean rips into Xaldin with even more force than the shift from Milliways to the World That Never Was did. This world is alive.
He's also not as drunk as he was then and so the pain isn't dulled as much. His scream is lingering and agonized; and it hurts enough that it's almost half a minute before he can consider calling up a wind to catch them as they plummet toward the ocean below.