I actually managed to beat it the second time. It's super random if you're lucky enough for the survivor to be within reach or not. Unless you mean level 4, where I couldn't beat it because of a collision bug with the box.
Viewing post in Attack on Survivor jam comments
If the collision bug you're talking about is the player being able to go on top of the box, that was a bug that I thought was cool enough to make into the solution for the puzzle. (Although I admit I never explained that concept to the player, so I understand your struggle and will introduce the concept more clearly next time.) Thanks for the feedback.