Completely wrong approach. Pre-compose the footage and inside the pre-comp clip away anything outside the green screen using a basic mask. Then try to extract a clean channel based on the green (use channel effects or the old basic keying effects, not Keylight!) and refine the result using other effects, then apply it as a matte.
Yipes! This won't be a one-step process. The green background is hot at the top and okay at the bottom. To pull a key in Keylight, I'd animate a garbage mask around the subject, and use Keylight to key out what it can. It won't be everything. Then I'd precomp it and use Rotobrush to get the rest and clean up the edges.
Rotobrush would be a waste of time. A quick mask drawn by hand is all you need. Animate the mask if needed. If one of her hands extends beyond the green screen for a few frames use a second mask to clean that up for just those few frames. Then set up something like this:
then some color correction for your original footage.
Thanks for the help - yeah this is an Adobe newb experimenting. Nothing more.