a few things:
whether its a plea or a charging decision isn't clear, but either way the reasoning behind it isn't clear.
"no contest" is called a nolo contendre plea, and i wouldn't allow it if i were the prosecutor. that is a sign of an office bending over backwards to let someone try to avoid criminal liability. i would want the civil case to be a slam dunk for the victim.
there may be restitution, but that is only for OUT OF POCKET expenses. in a civil case, you can get punitive damages, pain and suffering, etc. so he might have only had $5,000 in medical bills, but he could get millions from a civil case. this is why i think that it's reasonable for a prosecutor to consider ALL the possible benefits to the victim, not just what the max sentence is.