Might be worth considering getting the HLA-DQ celiac gene test for your daughter, yourself and her immediate family. If your daughter tests positive for DQ2.5, it is much more likely that together with her TTG result she has celiac disease. If she tests negative for DQ2.5, DQ2.2, DQ8 and DQ7.5, celiac disease is unlikely but not impossible.
Also, IgA...