Can I have a bulemic dachsund? Probably not, but I guess anything is possible.
I'm sure you are doing everything possible, I hope you get answers from TX A&M. Just a thought.... Do you suppose it could be the after affects from her surgery, you know until her little body heals completely. I know kind of off the wall. It is strange that she keeps everything down until the evenings. Maybe you do something different at that time... Different food? maybe too much at one time? Note, not saying you do I was just thinking of different things.
Maybe you can get her in tomorrow, I would tell them it's high priority and you don't want to lose her.