Oh gosh, how frustrating. First, WELCOME and congrats on your new baby - well, and your soon-to-come new baby, lol
! Bless you for taking in a 6.5 yr old yorkie.
It still sounds a bit like diabetes, with some of those symptoms - but it appears not to be. They did a fasting glucose level to confirm that, I assume? I guess I'd be asking for a full kidney panel to see if there is something wrong there. I would want them to re-test the urine as well. There is clearly something wrong w/ this baby and I do hope they can find an answer. She may need something for her tummy as well - pepcid, sucralfate, even Pepto can help. But, it sounds like there is a lot more to it than just this. Please keep us posted and all the best to you.