Has anyone seen the videos of the guy on the roof? People filmed a dude on the roof of a metal building.
There's another video of a guy being interviewed saying he saw the guy on the roof and reported him to the police 2-3 minutes before the shooting but they did nothing about it.
Most likely scenario, young cop thinks, "no shit there is a guy on the roof." Why? Because he was probably told to watch the crowd and never told where the overwatch guys would be setting up. So, to him it was just somebody freaking out over a Secret Service agent or a cop from out of jurisdiction.
I worked huge events and gatherings at a major college. That includes dignitary visits. The local guy on the concourse is barely fucking clued in. The Feds see him as a warm body and act surprised that he can breath with his mouth closed. So, the cop probably assumed that he wasn't told on purpose, or the info got lost in the pipeline.
Or, maybe they called it in and miscommunication lead to command saying it was one of their guys. So, everybody thinks it is settled and just gives a smile and nod as people keep reporting it.
There are a few common issues that could have lead to this.