When you get to the vantage point, get on an elevated surface where the ventilation unit is so you can have a better look at the points of interest you need to capture.
Point of Interest 1: Police Chopper
The first point of interest is the police chopper on your left. Zoom into it and take a picture.
If you've taken the picture correctly, you will get an option to send it to Jamal. Do that, and it will be registered as your first point of interest.
Point of Interest 2: Ventilation Unit
The second point of interest is the ventilation unit you see on the rooftop of the Mission Row Police Station. You can see a small blue arrow indicating what you need to take a picture of.
However, the ventilation unit on the right won't be registered as you're too far away from it. To take a picture, you need to get closer.
Stand by the ventilation unit and then take a picture of the ventilation unit on top of the police station. You don't have to take it from an angle above it.
Point of Interest 3: Rear Exit
The third point of interest is the rear exit. Go to the Mission Row bridge and look down towards the rear exit.
Return to the Salvage Yard to complete this scope out mission.
With the Mission Row Police Station scoped out, you're ready to move on to the Preparatory Tasks.