This is to give an idea of the slop and weight shifting after toe touch, losing the coil and not turning right away.
The first clip he is maintaining coil until the back leg/hip starts to turn and the body/hip is still coiled as the body begins to turn. In your DD case she is still shifting after toe touch. The ML hitter isn't shifting the body forward after toe touch, any shifting happens prior to toe touch. So she really isn't staying back, still coiled.
I'll be back
Is a lot of what you're describing here and showing in the images the all back/all forward problem (I think I see her doing that, though I've definitely seen worse)?
In other words, is "maintaining coil" another way to describe that "separation" you want to have between upper/lower half on the stride?