While I agree that suddenly forcing her to go on the escalator with no support is not a good idea, please work on this with her. Use a gradual approach to desensitize her--for instance, first look at pics of escalators, then watch YouTube videos, then watch peopl on them but don't get on, then ride a small one, etc. Push her just to the point of being a little worried every time and praise her a lot each time she succeeds. I spek from experience as an adult just getting over a truly bothersome and inconvenient phobia. My parents allowed me to avoid my fear for decades. It was absolutely the wrong approach and impaired me in my adult life.
