I have already posted about a similar issue in another mission, but this time it´s Marrakesh Gilded Cage. Finally I could try sniper assassin using the briefcase, where I would do both shots without entering any building and run freely around the map with the sniper packed. When I got to Zaydan, I got to the school master roof top, climbed the ledge and reached that other rooftop (with the axe carved into the air conditioning). I was completely careful not to be seen, did the shot with the Ghost sniper (silent) and even there were no alarms (not seen by anyone) I decided to wait 1 or 2 minutes for the guards finish the search so I could exit easily. However, guards are swarming the front of this rooftop, running like cockroaches and looking up. There is absolutely no way anyone saw/heard the shot. I can´t leave as I will be seen.
Had a similar disappointment in Mumbai, where I took a shot from FAR away and in 1 second the guards nearby the target start shooting at me. It´s like guards are superheroes when you use a sniper rifle. Shame. This looks like it was never tested before launching.