During the "Hey Hey It's the Monkeys" quest, Zeke should tell the player that some of the hidden items in this and future quests might be in buildings. By the end of Celestia most of us are used to having the hidden items be out in the open, and having that expectation defied once we reach Zemunda required looking up the locations, which some people prefer not to do.
Perhaps something like "And remember, some of these monkeys might be hiding 'round inside, so make sure you don't miss 'em!"