Yeah that is an option, but.. you can try something else...
Try to kill the all enemies around silently, dont make any noise and when you reach the toilets, walk silently crouched and open the door and u have about 1-2 seconds to see him until he gets alerted (1st picture)enough to make a photo... or you can try to glitch the door and you can stay in front of him without getting him alerted (2nd picture)