The shadow around the bottom of the fabric is what looks fakest.
This why you need to shoot against white, I think. So that you can use the natural shadows.
Well, I was wondering if there's a lab or camera store near you where you could hire a Spyder5Elite. It would probably be the best device for your situation, but it would be nice to test it before buying, you know?
When you double-click on the thumbnail of the Gradient Fill 2 layer, a little window pops up. Can you show me a screenshot of that?
It's completely ok. Post all you like.
Are you familiar with this method?
Use a nice big brush to clone out the whole top half of her head, if you have to. Clone way more than you need. The bigger the brush, the better it will blend with the existing background.
Then start the painstaking masking.