I would have punched him in the face. No one messes with my fish. >:(
I'm really sorry for you loss though. :( You did the best and only thing you really could. You can't reverse poisoning, the only thing that could have been done is what you did. Placing the fish in clean water.
And again, I'm sorry for your loss.
I can't give advice about the sorority because I'm not familiar with them.