Lypshynching Green Day SNL?

I can see what you mean if you were watching the second guitarist or the b player. They never appeared to get to the mic in time to sing the back-up parts. But next to the drummer there was a keyboard player who was singing back-up as well. And he appeared to nail the back-up singing every time. Easy enough since I don't think there's any keyboard part in the 1st song they played. So, if you heard him singing, but SAW the b player not really singing, I can see how you'd get that impression.