The only way I can see the driver not being at fault is if he 1) could not see the kids near the road, and 2) had no reason to expect people might be in blind spots near the road.

Given that there were houses less than 2 blocks from the site of the incident, 2 seems unlikely - this sounds like either a suburban or urban neighborhood (multiple crosswalks within 2 blocks for a 4 lane road). No mention was made of any obstructions, which is not evidence in itself; but it's the rare four lane road that hasn't had obstructions cleared from the sides of the road (partly for this reason!), particularly in a non-rural area. At a glance, Gastonia seems to generally keep their roads clear.

I can certainly be convinced otherwise with more evidence, but the burden of vehicle safety absolutely lies on the driver. If you can't respond fast enough to a seven year old running out in front of you from a place you can't see; you are, by definition, driving too fast - regardless of the posted speed limit. And if you can see them, and aren't driving in such a way as to be able to keep them safe should they run in front of you, you're driving recklessly.