I'm well aware where SAC is located and what the surroundings look like. But those pictures were clearly not taken from a high-rise, they are at relative ground level.
Being in the city center doesn't prevent an organization from shielding sensitive activities. Simple countermeasures such as raising perimeter walls, adding visual barriers or netting, planting dense vegetation, installing temporary screens, patrolling guards or even just cameras can make photography extremely difficult. The fact that such straightforward measures weren't used, even after almost identical earlier leaks, makes it hard to believe that these leaks aren't either allowed or at the very least tolerated.