It sounds like that when they were innovating her(putting the tube down her throat) they didn't check to make sure it was in her lungs not her stomach. It is not hard to misjudge that. You are aiming for a lil flap over the trachea that has to be pulled down then the tube inserted. If you go a little to the left or right you miss and go in the stomach it feels the same way going in. We used to have to double check this by giving a gentle push on the rib cage to make them expel a breath which you should feel coming out the tube if you didn't feel the puff then you knew you were in the stomach. This is just my opinion but that is their error and not due to the dog swallowing I wouldn't let them touch my dog again. Also find out who inserted the tube 9 out of 10 times it was a tech not the vet. They would be caring for my dog and not charging me anything.
Mind you this my expierence from years ago as a tech....
Mind you this my expierence from years ago as a tech....