At the 7 minute 50 second mark, an alternate version of the Hall of Hieroglyphs' music can be heard as one of the credits tracks. To my knowledge, you get this by beating the game with 0-1 chests in order to get the worst ending, with Shokora appearing as a baby.
Thing is, I've seen this track around claimed as an 'unused' one, but it turns out that it's used by way of the credits level tracks that are played.