Drop third strike with two outs.

[SC Ump]

I had a strange one on Tuesday in a high school game. Two outs and B3 swings at a ball that bounces into the catcher's glove. The catcher rolls the ball back to the pitching circle and the defense leaves the field. B3 walks toward her dugout on first base side as I'm watching her. As she is about one step from the dugout her coach said, "Run to first." She does and since she had never entered the dugout, I ruled her safe.

(Note: she never removed her helment, so I did not have to give a team warning about that.)

Here's the question. What if B3 never entered the dugout before taking her position on defense. At what point should I rule her out. I thought perhaps when she took her position on defense, but was wondering if that was waiting too long if the coach has a little huddle outside the dugout. (Coach's in SC still do this since we have been asked by the high school league office to allow this if it does not delay the game drastically, and to not stictly enforce this year's point of emphasis about no huddles.)

So, I'm interested in your thoughts. When is the batter out if she never enters the dugout?

By the way: yes the defensive coach argued. He never stated that I had it wrong, only that he thought it should never be the home plate umpire's call to rule a dropped third strike, it is always the base umpire's call. He knows this because he use to be an umpire for a long time.