Other mistake: When Dennis Quaid fires his SIG-Sauer P229 pistol on the bad guys under the over-pass, he fires 28 shots from a 10-12 round pistol without reloading.
Other mistake: In the last scene under the Highway, when POTUS thanks Barnes for saving his life again and when the camera starts zooming out for the end credits, in the traffic driving above the accident there is a Mexican green taxi cab VW Beetle passing through. But, the whole movie takes place in Spain.
Other mistake: During the car chase scene, the Opel Astra (blue car) repeatedly collides with other vehicles and objects on the front end, yet the airbags don't deploy.
Other mistake: When Barnes first gets into the Chevrolet Astra (blue car), he pursues the police car but never changes from first gear, as he has one hand on the steering wheel and the other holding his phone to his ear. Without a gear change he'd never reach chase speeds, plus the engine strain would be easily heard.
Other mistake: When the Secret Service agents are running after the Spanish cop, they are running and shouting with their weapons waving in the air, yet the group of Spanish police that they pass don't try to challenge them.
Chosen answer: It's not stated in the film, but if I had to make an educated guess I'd say his job is to make sure the news channel doesn't get any footage of any of the terrorist agents or the window the shots come from.