Sperg theorizing.....
Guy probably had a change of clothes and some clean up supplies in the backpack. He was probably not stupid enough to have a phone on him and if he did a burner phone. His time of attack is when its normal to see foot traffic but not a bajillion people in the way.
He compotently cleared weapon jams and kept composure the whole way. You can see him check on the guy briefly and "make sure". He didnt run away but strolled off and went straight to a bike and went to central park where cameras lessen.
He most likely changed clothes cleaned himself up. Burned those clothes, shoes, and backpack in a fire and dropped the weapon in the central park lake. He may have had padded clothing to mess up profile matching. He may be bald and wore a wig ad well. All of that burned in a trashcan fire that homeless in central park set all tye time. He then strolled out around 8am looking like all the morning run fags and went straight to his hotel and checked out at a normal time, caught an uber. (His phone was there all night and some automated behavior gives geo data to point him being there so he doesnt get tagged in phone data searches) Got on a plane to somewhere else in the US (overseas flight would get scrutiny) maybe taking overseas flight from the next step.
As much as we cheer this on. Screams pro hit. This feels like lizard person on lizard person action and its likely some worse shitter benefitted. The stock going UP on an assasination of the ceo is suspect as well.