You've got an interesting touch with what happened to Vince and his friend and siblings (though that seemed very random, and the other friend's death seemed a bit contrived), and with them being test subjects that, for once, don't hate the scientists working on them. You do still have some things to work on, though.

Mostly, you had a lot of grammatical errors; tense swapping, missing words, wrong words, that sort of thing. For example:

"The neurite [had] completely rewritten how their bodies functioned."

"[...] allowing them to send a beam of accelerated neurite to an object, and implying it isn't rigid or too heavy, could lift it." Maybe "implying" should be "provided" or "so long as"?

"[...]involving the four to work together[...]" should be "[...]involving the four working together[...]"

There were also some clarity issues. For example:

Where is the neurite visible (or clarify that it's signals to begin with), and is there a reason it has different colors? If Will's is black, why is he called White?

Clarify that it's two decade before they woke, not two decades before they were hit.

"Anything their brain thought, the neuroxide thought as well, except with one difference." So it's still separate from their brains and is, itself, alive?

"The neuroxide-infused brain could send a purple-colored beam of accelerated neurite through a permanent scar in the host's right palm[...]" Does this mean they can make others like them? And are they draining the nuerite from their bodies?

Some of your words also seem a little weird. I was confused by "quad bike" as bicycles are 2-wheeled; it's even in the name. "Neuroxide" seems a bit odd too; that simply means it's neurite and oxygen that have chemically bonded, so I'm not sure if that's what you meant or not. And, although I think it may just be a lack of explanation, Vince stuffing an air conditioner into his nostril seems bizarre.

Your age calculation is flawed. He apparently stopped aging at 14, so that's assumably when the neurite hit them. They were then in a coma for 2 decades, which was followed by 30 years of testing. That makes him 64 years old, not 38.

You should also work on your characterization, especially since that's the main focus of this tournament. Your character doesn't seem to have a stable personality. He wanted to win the race for his siblings, believing it would somehow improve things for them (though they seem to be doing just fine), and is willing to risk his life for that; and then, when he finds out he's in, he just shrugs it off like it's meaningless. Your characterization of Domumen is also weak; you wrote him as business-oriented and perhaps a bit of a jerk, rather than eccentric and charming as in the prompt.

Keep working at it though, and you're sure to improve. Good luck!

My review has been submitted for consideration in "Good Deeds Get CASH!" .