@minajo I am so sorry to hear you and your daughter are struggling with so many issues. It's very difficult when your child is non-verbal. You have to be able to read their body language and know them like you know yourself so you can pick up when somethings off. I know you are waiting on an "official" diagnosis of celiac disease. You did mention your daughter was lactose intolerant when she was a kid? Did you have her on any special diet then? Has she been tested since? I know it's difficult having to implement a special diet in a residential home. How receptive are the providers? Has she ever had an endoscope?
My son Keegan is 28 now. He also has autism, cerebral palsy, is non-verbal, and was diagnosed with adult-onset Epilepsy. Growing up, he had many GI issues and still has a few but they are much improved. Growing up, Keegan's gastroenterologist performed an endoscope every year, for over 7 years. Keegan has intolerances to certain foods (not "true" allergies) but certain foods affected him and he had a leaky gut. Keegan's endoscopes showed GERD, gastritis, eosinophilic esophagitis, pancreatic insufficiency, a peptic ulcer, chronic constipation, and a "previous viral insult" to his small intestine that nobody could ever figure out. We had Keegan on a dairy, casein, wheat, gluten, soy, and corn free diet for 7 years. As he got older, his endoscopes were only showing reflux. We reintroduced foods, one a time, for 3 months at a time to see how he did and if he had any reaction. He's now able to eat most anything but it took a lot of time.
One thing you mentioned was your daughter has a recurrent cough and upper respiratory infections. When Keegan was younger, he had chronic "phlegm" and ear infections. We found out it was related to his dairy intolerance. Once we removed dairy, all those symptoms stopped.
I can't speak much on the estrogen replacement. It's a difficult situation you and your daughter are dealing with. As far as the providers in the home, do you have a good relationship that you can work together and create a diet that's appropriate for your daughter? I would also recommend talking with your GI about an endoscope, so you can see what's actually going on inside. If you do end up implementing a diet, I would make sure you have the providers journal what foods she has for breakfast, lunch, and dinner. That way, if she's having a reaction or her behavior is off, you may be able to pinpoint what's causing the issue.
I hope this has been helpful. Just know, you are not alone and you will always have support here.
Kerry