Maybe you could give the driver an Alertness roll to see if he notices the impending attack. If he succeeds the Alertness roll he gets to make the Driving roll to try and dodge, if he fails the Alertness roll he doesn't. Even at Supernatural Speed he'd have the chance to catch something "blurring" out of a truck and heading right for his vehicle. That's the point of the Alertness skill, after all. Though in this scenario I'm not sure what the opposing roll from the PC would be, as he's not really being Stealthy. Maybe just a set DC from you as the GM would work.
We have to be careful here.
1 There is nothing in the game that prevents you from making dodge rolls. The closest thing is Ambush and, even that, you still get to roll, albeit at a +0.
2. There is nothing written in Supernatural Speed that says the person is so fast you can't defend against them. it does not give you free ambushes. It does, however, let you do stealth rolls where you may not normally be able to.
So, if the character wanted to say "I jump out stealthily and charge the jeep for an ambush" I'd say, "sure make a stealth roll against their alertness. They get a +4 bonus because you are sprinting at them." 'x' number of shifts of that penalty are negated by Supernatural speed. (I forget what it is...4 shifts?
3. To quote the OP
The faster than perception PC jumps out of the truck
Supernatural speed does not make you faster than perception. You
can be seen.
I assume the Jeep had stopped? If the van was disabled, then the Jeep would have to slow down or stop moving which is the only way I'd let anyone attack the Jeep. Otherwise he has to spend his whole action keeping up with the vehicle. Even mythic speed requires you to use your action - you just don't have to roll the dice.
I think I would have done it this way:
Bad guys open fire, truck gets disabled:
Initiative: Supernatural speed guy goes first.
He moves 1 - or 2 - zones as a free supplemental (I assume you let him smash through the door with his supernatural strength instead of taking an action to open it?)
He attacks. He gets two options:
1. attack with fists. Resist with drive. The Jeep has armour - probably 2 or 3 - (I assume it was a military jeep), Military Grade weaponry is probably quality 3-5, so it has at least 4 stress boxes - and possibly, a consequence or two.
1a)If he takes the Jeep out, I'd probably make a separate attack on everyone in the Jeep, letting each person make a roll to avoid but let them replace their dodge with the driver's drive roll which he'd do to resist the attack. Their armour would apply to the attack.
1c) continue down the initiative list. The baddies have to take actions (supplemental or otherwise) to get out of the car but have armour against attacks while they're in there.
2. Let the PC do a 'breaking lifting' check. Take the driver's drive roll and add that to the difficulty to 'break' the jeep.
the break DC of an armoured Jeep is probably, at least 7 or 8? A regular car door is 6. Being able to actually knock the Jeep off the road would be harder. The lift DC of a midsized car is 9...so it's probably higher. but since he's not lifting it, I'd put it at the equivalent of, maybe, 'moving it one zone?' I dunno....hard to know... so, I'd say, you need to meet that difficulty or beat it by 2 shifts. So, a 10 would do, but I'd add the driver's skill to that.
2a and 2b same as 1a and 2b
I might compel an aspect, if they have an appropriate one, to have the PC take a hit against the car. I've seen a Pickup t-bone a car....the pickup was in rough shape.
So, having spent a day thinking about it, that's how
I might run that situation. Probably different from how others would. The point is, taking out the car doesn't take out everyone in it automatically.
I had one of my own PCs do this exact thing with a character who had Supernatural Strength. I forget how we did it exactly, but it was an ambush and I had an option to walk out in front of the car, and try to obliterate it, but I'd have to take an attack from the driver. Instead, I hit it from the side with a giant hammer....not sure how the GM adjudicated it...in any case, I still had to fight the people inside the car.