On the level
"Damn! It's late". You will eventually come to a point where you're
on stage with Johnny, and he's explaining to you how they're shutting it down for the night due to the aliens and etc. Literally right after this when you walk backstage, there'll be a
guy in a black jacket yelling at another guy in a blue shirt. Walk up to the guy in black and simply
to melee (punch) him and wait a few seconds, trophy is yours.