if you watch the video he was trying to subdue her hands, which is why she resorted to kneeing him. There is a significant amount of time between the take down and the knee to the head. -he wasn't fighting back at all.
This wasn't MMA, she was pulling on his hair, when he immobilized her hands, (which every guy knows is normally followed by a kick to the crotch), but instead she knee'd him in the face because he was going into a fetal protective stance. What he should have done was to put her in a bear-hug submission body lock instead.
https://www.youtube.com/watch?v=n4fKB-DOM_A