Unfortunately, ultrasounds aren't that reliable (as low as 60%) for diagnosing shunts. Most vets just don't see enough cases of liver disease to be up to date on the current protocol for diagnosing and treatment. You can waste a lot of time and money with your regular vet. I would definitely take her to UT.
Was a Protein C test done? That is the next step after a high bile acids test, not an ultrasound.
Comparative Coagulation -- NYS Animal Health Diagnostic Center