Didn't seem very funny to me. Hey, let's make some guy scared that he's about to get beat up. Make sure he's a minority to ensure he over-reacts out of fear that he'll get assaulted and nobody will intervene. Hilarious, really. Really?
I'd have laughed if the victim had punched the comedian in the face, because that would have been funny, a stupid joke backfiring is classic comedy. Making someone scared they'll get assaulted is, in fact, assault. The fact they got it on tape pretty much ensured that the "joke" victim could probably win a civil lawsuit for assault against the comedian and his accomplice. That would be funny too.