geno is the starter, other dude was a broke backup.
it'd take a lot to just sucker punch the QB, and the released-player says they were both involved in the fight.
I bet in the coming days, we'll learn Geno shoved the dude, and dude swung back and broke his jaw in 21 places (as they're reporting now) with a single punch/fall. I highly doubt he just crept in and silently swung on geno, I'm betting there was shit talking going on. Dude was mad his camp got punked when Smith bailed last minute due to friend killed on motorcycle.