I see where you guys are coming from but whenever I get dispatched to rollovers in real life, for example, we always have to assume that it is one. There's not an alarm system like buildings have. So to me it makes perfect sense that it can simply change to road accident. Sometimes callers are panicked and exaggerate the details of what actually happened
I'm also a firefighter and that's where I want to get, people exaggerate and then it's just a little thing.
The point is, sometimes you will not know how many victims you have and it will work like the fire alarm, you just know when you get there.