gavra:
You said: Who knows better, the expert who knows the case and has studied the field or the Rav who does not?
tal already answered this point of yours, prior to your comment: SJS, I think you may be convincing yourself that Rabbanim respond in matters they feel they are unqualified… Rabbanim don’t speak when they are not certain… and see tal’s entire comment above.)
You said: The rav can tell her she is a Moredes if she does not go to him. Then it is her choice to go or not.
No, its not a matter of choice. If she is a moredes, she is obligated to take corrective action to ensure she is no longer moredes. (If she fails to, there are consequences. But she was still obligated to stop being a moredes.)