This is how Yuna and Dusty telling Duncan and Cranky stops RMS Titanic II goes in Yuna and the Monster of Blue Mountain Quarry.
Later, Yuna and Dusty saw Duncan and the flatbed of scrap.
Princess Yuna: Duncan! What is that?
Duncan: Nothing. That was just a flatbed of scrap that was left on the line.
Princess Yuna: (gasps) Duncan! You played a trick on Luke!
Dusty Crophopper: You set Luke up!
Yuna: You made a monster out of scrap to give him a fright!
Duncan: How'd you two know?