I was kind of surprised that your doctors want you to do the barium swallow test. I had one, and it does require you to drink some thick fluid. If you can't swallow to begin with, I don't see how this test can be performed, as the liquid is tracked throughout your upper GI tract.
Have you had an endoscopy? It is where you are put to sleep for a real short time and they take a camera and have a good look at all parts of your throat and stomach. You also may get a biopsy. I am curious as that seems like a good investment in research into your swallowing problem. since you are asleep there is no resistance of your throat to the proceedure. I sure do hope things improve for you. What field of expertise is following your case? I will continue to keep you in my thoughts and prayers. ginnie