The reports seem to indicate that it was at Cutter Aviation. If so there is not much “trough the fence” plane spotter view.
https://www.google.com/maps/@33.4256534,-112.0228943,421m/data=!3m1!1e3
If private field they can decide to take photos or not by themselves. They are not bound by some federal agent that has no authority over the field.
If public field, federal agents have no unilateral authority either.
The airport manager could act on his own discretion to follow of not follow federal agent directive about photos.
To presume federal agents have unilateral power to ban photos of something happening in plain view is something I can’t see as a legitimate use of power—and it is not either.