I had an interesting situation in an 18U rec league game last night. Runner on first, and batter swings and hits the catcher's mitt. She also grounds the ball to F3. F3 picks up the ball, steps on first base, and then throws to make a play on R1 at second (BTW, because of what I was told here in a recent discussion, I didn't kill play as soon as the obstructed batter was retired

).
In true fashion for rec league ball, the throw goes over F6's head. F7 retrieves the ball, and throws to F5 to play on R1 who is now trying for third. R2 is safe at third on the throw.
I call Time, go to explain to the offensive coach that I had catcher's obstruction, and offer him his options. He decides to go with the penalty to put runners on first and second. Out of the dugout comes the batter to occupy first.
So now I remember that a rule (ASA 8-2-D) calls for a batter-runner to be called out if she enters the dugout area after a catcher's obstruction. But I can't imagine that this would apply in this situation, since the batter had no idea she was obstructed. I let the runners take their bases, and played on.
I checked the rule book after the game, and found 8-2-D. But it provides no guidance how it applies.
So, why does the rule on a batter entering her dugout include catcher's obstruction? How is she and her coach supposed to know the obstruction occurred, and she's supposed to stay in the field of play until the infraction is adjudicated?