The trouble with antibody tests is that though they prove T1, lack of antibody does not disprove T1. This is really a question that you need to ask your clinic. DKA is deadly without treatment so my advice would be to listen to your doctors on this. (Plus we aren't doctors here and forum rules say we can't diagnose.)
I'm so sorry your DD has T1, but I promise you that treatment now is infinitely better than when I was diagnosed at 8 in 1970 (and I'm still alive and well and T1 has not prevented me from doing anything I wanted to do in life.)
Good luck to you both.