They're still using red and green? In a school? That's the most basic colorblind combo to avoid, it feels like we learned that ages ago.

I mean, that's a funny story and all, but idk if I'd call that a mistake showing your fit. It sounds more like the boss just had a good sense of humor about an accident. Maybe it's just me, but a real mistake that shows fit would be like, forgetting to restock something but then figuring out a faster system to prevent it. The ketchup thing is just a lucky break where the person in charge didn't get mad. It shows their character, not really yours, you know?

Totally agree with @samschmidt, a solid seam is key. I double-cut mine with a sharp blade and they've held up perfectly in our main hall.