[SanDiegoSteve]

First of all, you are looking to a MLB rule for Little League. These two sets of rules are not the same. Little League has their own rule book, based somewhat on Official Baseball Rules (OBR).

Secondly, if the runner was in fair territory, and hit by a fair ball, then he is out, and the ball is dead. See rule 7.08 (f). The only exemption from being out when hit by a fair batted ball in fair territory before the ball has passed or touched an infielder is if he is standing on his base on an Infield Fly.

Since this was not an IFF situation, the runner is out if he was hit by a fair ball in fair territory, whether or not he was standing on a base. Now, this teenage umpire called it a foul ball, which while possibly incorrect, was the call he made. It is a judgment call, so it can't be argued or protested, even though it looks like he made the call just to get out of actually giving a proper ruling on the play.

In "real" baseball, the runner would have been leading off the base in foul territory, and this situation would not have occurred. But since this is Little League Baseball®, there is no leading off, and the likelihood of the runner being on the base or over the base in fair territory is greater.