Hi. Has she seen someone who has assessed her musculoskeletal system in her neck. There are certain muscles, that when tighten/spasm will cause pain that radiates into the ear scalp head area. One muscle in particular that can cause pain behind the ear, and attaches in the mastoid area. These headaches that start from the upper cervical area can cause all kinds of odd dizziness/pressure sensations, and often times you can not tell it is coming from the neck. ENTs are supposed to be educated on the Jaw area and how all of these muscles can mimic ear/sinus pain. But unfortunately most are not.
Just a thought.