The barium test should be extremely accurate for discovering a blockage. As the barium passes through the system the vet can see if it stops or if there is an narrowing or ulceration.
We haven't had an endoscopy on any of our and would only do an exploratory as a last resort (anesthesia risks).
I noticed in some of the postings going way back that you were considering a vet change. Have you considered obtaining Timmy's medical records and seeking a second opinion?
BTW, heading to Purdue in January! BoilerUp!
