I don't get it. Is there a setup?

they don't despawn, WR does the level in a way that they're facing left when the button that frees them is pressed so that they're off screen and not in front of the goal when getting the last shine.

thanks for the explanation! i think ive got it down now, i just need to get better at level 7 and have a lucky bowser so that i can achieve my goal of sub 3:30