I'm a little confused about which elements here are true actually. Did he piece together pieces of factual history to create a plausible scenario? And if so, was there ever a flash mob that resulted in a riot which lead to 23 deaths?
Upload to live news < 24 Hours - Epic Beard Man
Short Notice Flash Mob - Mass Moonwalk 2009
Personal Details Leak - Alex Wuori 2007
Flash Mob to Riot - Gallery Mall Mob 2010
http://en.wikipedia.org/wiki/1992_Los_Angeles_riots
(Just a history lesson. I agree with you that it's a huge stretch)