DD catches Fly #1... throws to 3rd basemen, steps on bag #2 (force player running from second) tags player trying to return to 3rd... #3 ...
It looks like your DD catches the ball for out #1, then throws to 3B who steps on bag for out #2 (base runner who went home), when the runner from 2nd base steps off the bag at 3B she is tagged and called out for out #3 (watch the umpire ring her up). If the runner from 2nd had stayed on the bag, your team could have thrown back to 2nd base to appeal her leaving early and she still would have been out.