That’s kind of how allergies are discovered though. Doctors will tell you to go on a restrictive food diet and tell you to binary search for it if it doesn’t cause anaphylaxis. Based on my experience with allergies if it’s not anaphylaxis then allergies aren’t considered super important to resolve by doctors. Finally the immune system is complicated and your daughter may have an unusual reaction which may not be IGe mediated. In other words it could be a reaction to a foreign protein and not an anti-body histamine spike in which case: yes it’s extremely unpleasant and feels like an allergy, but because it doesn’t lead to anaphylaxis it’s not a medical concern.