Replace every tick with:
Is "Willbur..." Not playing "idle" animation: Move forward
This condition runs every tick so you don`t need to have every tick condition
edit: let me explain what changed
Instead of move your sprite every tick, now, you first compare the animation to see if it is not playing "idle" if it is not, then move it forward.
When it colide it will change to "idle" animation and the first condition its no more true so it will not move anymore