SS, I also suffered very bad digestive issues for several years, and I saw multiple gastroenterologists. They were quick with the prescription pad and the expensive diagnostics, but none of them ever made any suggestions about diet. The doctors themselves were overweight and unhealthy. The only advice I ever got from them that had any effect was to take metamucil. Thank goodness I avoided taking their dodgy pharmaceuticals and discovered the PB instead. Changing my diet cured everything. If I had just drugged away the symptoms, as they told me to, I would be much worse off today. My own grandmother, who had the same symptoms as me, died from necrotic bowel after being treated by these geniuses.
If you can find a primal gastroenterologist, I will be amazed. What kind of modern doctor tells you "oh you don't need all these prescriptions and colonoscopies, just try cutting sugar and grains for a week and see how you feel." I have a feeling such a doctor's business would be at risk, if not his license. But who knows; maybe there are some sane voices in the NYC wilderness.
I would hate for your friend to get stuck in the same Big Pharma dead-end as me. I wandered in that desert for seven years. Fortunately, as a lacto-ovo-vegetarian, she does have options. You could do a lot worse than fried eggs and kefir. Perhaps you could convince her to try excluding certain foods before she makes herself a ward of the medical-industrial complex?