The ‘official’ version is on wikipedia and is a bit wider (uncropped). Even to my untrained eye, it just jumps out as a layered composite of single individuals or clusters, to create the illusion that they were all there together at a single moment/event. Each person occupies their own optical plane, there is no overlap or adjacent shadowing presumably by stark office lighting, and boundaries between humans and their clothing is too sharp and contrived.
Is that why the guy in blue in the back by the door looks like he has his own light source?
"The ‘official’ version"