First of all, your boss was injured because someone failed to yield for him, not because he was on a road bike. He could've been on a bmx bike and the same thing would've happened unless he was skilled enough to hop over the car.
Second, I really think you should give the road bike another shot. The reason is, it's going to be a good 20% lighter than the other bike, it's going to accelerate faster, you'll be able to keep speed faster, it'll be more aerodynamic, which all adds up to you being able to keep up better with traffic. Otherwise, between the vita sport and the fx (the vita sport is more comparable in specs and price to the fx), I'd choose the specialized. The specialized has a lighter frame.
Along with that, keep in mind that staying safe out there isn't always relying on the other driver to see you, it's about keeping your eyes open and being alert. One interesting statistic is that most people who are killed on bicycles in NYC are regular people. The messengers who are out there every day riding anything from cheap bmx bikes to fixed gear track bikes with no brakes usually aren't the ones who get killed even though they're riding 100x more than everyone else out there, and sometimes a lot crazier too. There's a reason for that.