I'm sorry Stan, that sucks.
If it is any consolation to you, the Gamma Omega chapter serenaded every fraternity and sorority except one, and that's because they are about 1.5 miles off campus and too far to walk!
I am only speculating here, but I'm guessing they were turned off by the animal house rep. I know that our internationals has been really pushing us to watch who we associate with in any manner. I'm not sure if this is true of other chapters or just mine (we are the only NPC org on campus). They still should have made the effort though, and I'm sorry that they didn't.