weird situation. is there any ethics consideration here?

[Torello]

Look this is easy. If he wasn't messing around and showing cards, and the hand was straight up, there's a 100% chance you would stack him right?

Why should his messing around cost you money? I could see not taking an extra advantage off of someone's kindness, but this is not that. You stacking him is what this hand is meant to be, and it's not fair for you to give that up.