did you have a full blood panel and were her alt high as she may have liver shunt which runs in yorkie breed and not many vets are aware of liver shunt. You need to have a pre and post bile acid test and protein c test done immediately as she could have liver shunt at her young age and the surgery is very successful if you go to dr tobias at university of tennessee -I would only trust her with that surgery and no one else. Dr center's is the internal medicine specialist at cornell that has done a lot of research on this as well. Dr tobias is the surgeon - only trust them and have vet run the tests
fast her for 12 hrs pull blood feed wait exactly two hrs on dot then pull blood and that is a pre and post bile acid test. The fact that your vet did not recommend this immediately on her being a yorkie i would get to an internal medicine specialist and as your vet who is the best in area and go this person to run the tests for liver shunt
is she a picky eater, head press against wall, acts spaced out after eating? These are signs of liver shunt. Vomitting after eating? What is protein % on food as you may need to get protein count down to 18% but first get the bile acids and protein test done immediately as my gut is this is what is causing the seizures in such a young dog. I think she is too young to have epilepsy
was the breeder you got her from reputable