I think in your search for a contrary example, you're looking at it in the wrong way. The focus of the unlucky pessimist will lead them unerringly to the stairs, whether or not that's the best option. The lucky optimist won't foolishly do what no one should ever do, but instead notice that the open elevator shaft has a ladder that someone else just safely used to escape. Being lucky doesn't mean you have to be stupid.
The unlucky pessimist will stand in line while the lucky optimist will notice that what she needs is easily obtained out of the line.
Take this thought experiment to its extreme and the unlucky should have gone extinct. The fact that both lucky and unlucky personality types persist, suggest both have advantages.
The unlucky pessimist will stand in line while the lucky optimist will notice that what she needs is easily obtained out of the line.