Base award on passed ball

This scenario happenned in my son's Middle School State championship game last week.

Count is full, runner on first base. Runner takes off for second base on the pitch which was in the dirt for ball 4, the ball bounces away from the catcher and goes down the 3rd base line and rolls out of play (just behind the backstop actually...not throught the backstop but kicked out and rolled behind it). The umpires leave the runners on 1st and second. My contention was that they had 1st and second on the walk and were entitled to another base for the ball going out of play. The runner on first had rounded second before the ball went out of play as well.

Did the umps make an incorrect call?

(It ended up not making a difference as the next batter popped up on the infield to end the inning anyways)