dropped 3rd strike and advancing runners

Question
U-12 game....1 out bases loaded. BR called 3rd sttike dropped runs to 1st...catcher follows her down first base line and throws to first.... runners on 2nd and 3rd advance at own risk. 3rd base runner who crossed plate called out ....2 base runner advanced to 3rd, 1st base runner advanced to 2nd while ball being thrown around. All baserunners (now at 2nd and 3rd) called safe and BR awarded first. Run did not count....out given at home even though neither catcher nor ball at home. Why would the BR be awarded 1B when technically she did not have the option to run to first due to 1B occupied? and why out given to scoring runner? and if scoring runner out why can all other baserunners advance at own risk but not one is scoring position? if this is indeed the correct ruling is it in effect for u_12 and up?
Thanks

Answer
Hi Courtney,

..catcher follows her down first base line and throws to first"  she shouldn't have done that, it is up to the defense to know the situation, none of this happens if she just throws the ball back to the pitcher, D3K is not in effect.  bad defense and bad coaching

"3rd base runner who crossed plate called out" why? no idea

"All baserunners (now at 2nd and 3rd) called safe and BR awarded first."

no batter is out, the D3K is not in effect

Run did not count..I have no idea why.

Why would the BR be awarded 1B when technically she did not have the option to run to first due to 1B occupied? and why out given to scoring runner?  Really bad umpiring by someone with no clue of the rules is my guess

why didn't the coach protest this?

Mark