I am not sure I would call a natural survival instinct ‘cowardly’. Its easy to quarter back on this one. Did the cop have a vest on, was he/she ready to be looking down the barrel of a rifle? Not all cops, actually only a few, train enough to have natural instincts to run into a line of fire. That takes a lot of stress inoculation to get to that point, especially if your hands are tied up trying to climb over a building ledge rather than free to draw your own firearm.
True- self included, most here know (if they know about this kind of situation or have been in one similar) what they would have done (or rather,might have done). Absence or presence of a ladder (which is visible from overhead google photos zoomed in)— the ladder may not have been in line of sight, for hands free pop and drop.