She is pushing the ball. Loosen up and let it rip! Loosey goosey full of juicey!
Just be careful that she isn't trying to rotate from a supinated to pronated hand position. Lag and lower arm rotation are a result of keeping the lower arm loose and the timing of IR in the upper arm.
It's so hard to learn over the internet! Hoping you can get into see JS again or over to see Rosey. Wish I was in that neck of the woods!