See the above response, maneuver the truck to where the final can be seen, there is no requirement to remain aligned with the taxiway line. In the medium/large CFR trucks, the driver sits in the center/left of the cab. If it’s a four person cab, there’s a jumpseat to the left of the driver next to the left door situated slightly aft, another seat directly to the driver’s right; and a jumpseat next to that seat and next to the right door, also situated aft. The two center seat crewmen, driver and other crewman, have the best view all around the truck from 9 o’clock to 3 o’clock. Some trucks have a roof hatch with a crewman who stands up through the hatch manning the upper turret and has a 360 view around the vehicle from the top. Either way, there’s ample ability to see what you need to in that 9-3, including the ability to position the truck to account for any blind spots. All airport firefighters know what they should be looking for in terms of threats. Knowing what goes on during emergency responses and having been there myself any number of times, I wouldn’t be surprised if adrenaline and distraction led to either not checking/clearing the final visually, or doing it in a quick manner. Again, this remains to be seen.