He might just curl up. Almost does. Not quite enough energy for it, so he divides it into relaxing but not going totally limp. It would just make it that much more difficult for Iruka to haul around dead weight.

He waits. Listens, wants to make sure the hall is clear before he speaks.

"They won't expect the front door." he croaks. Especially since Itachi's own habit was window escapes. It'll be the first area they check if they don't notice the note and think they can catch him.