Harumi's page says that "At the library she found a map that would take her to the Mask Of Hatred and once Sons of Garmadon captured Misako and the infant Wu she stole the map and wrapped it around Wu so that the Ninja would find it."
Where did the other map in the boat which she and Lloyd used to look for the mask come from?
They might have did, but it could have still oringnaly belonged to Yost. They could have just simply didn't discover the map (I mean, why would they think there was one?). Or perhaps they didn't use it and the logo was a mark, to show the Ninja that they were already there.