Some people are just uncomfortable with this sort of thing. I'd say it's different from youtube because they in fact are just looking for something to complain about. I think ADEE just wasn't expecting such a graphic serious of images.
Jacob, I'd say your heart was in the right place, but I wouldn't have chosen your methods. Cervical dislocation or chest compression would have been more humane, but I doubt you knew that. Cervical dislocation can be done wrong, and is then also inhumane. Chest compression (not chest compressionS like in cpr) is where you feel for the animals heart and compress the rib cage at that point stopping the animals heart. I was taught this method in a mammalian ecology class when we had to catch wild rodents and prepare type specimens. I believe it is said that it can be safely done to animals up to 15 lbs?