(hugs) It's hard when your babies aren't well.
You daughter did not have the proper celiac tests done.The serum (blood) IgA and IgG tests are like control tests for different parents of the immune system in the body. The total serum IgA is often run for celiac testing because a high proportion (1/20) of celiacs are deficient in IgA, compared to the regular population, which will affect celiac tests based on IgA (like tTG IgA, DGP IgA, and EMA IgA).
IgA deals with the part of the immune system that is in the mucosal lining, and the IgG (immunoglobulin G) is more of an systemic part of the immune system.
DGP stands for deaminated gliadin peptide. Endomysial AB (antibodies) is the EMA IgA. Anti tissue transglutaminase is the tTG. The old AGA tests are anti-gliadin antibodies.
Can you get them tested with DGP IgA and DGP IgG? They really are superior tests for kids. If you can't get any more testing done, you could do a gluten-free trila of a few months. If their health improves then you have a definite answer. If they do not go gluten-free, they should be retested every couple of years until at least adulthood as celiac disease can appear at any time - which usually just means that their antibody levels are finally high enough to be detectable. Hopefully tests will improve in the future.