I have seen genetic testing hold up in court with a patient. Genetic testing is very easy to interpret. I will be posting a video next week on this very topic. My advice is to find a doctor who will give you a diagnosis for your daughter. That that will hold up in court regardless of the testing procedure done. Elisa Act is your next best bet. Just keep in mind that allergies and intolerances are not the same thing. Elisa Act measures delayed immune response (allergies) not intolerances. Unfortunately, no definitive testing exists for corn intolerance.
Hope that helps. Keep us posted.