So sorry you're having this go round in diagnosis limbo, Patricia! Doctors can sometimes be a real pain. I've got no advice for you on the Enterolab tests, just lots of sympathy.
What does your GI doc think about the Enterolab test? I almost hate to suggest it, but if he does feel gluten is involved despite all the negative tests, maybe he could do a gluten challenge and use the results as a diagnosis.
Hugs,