GREAT news on the Stim, YAY!!!!! So glad you won't have to go up on the Mitotane, this is wonderful.
For the "bile test" you're asking about - they likely did a Bile Acid Test to check her liver as so many yorkies have liver shunt (esp. small ones).
I think it's smart you canceled her teeth app't. - what a good Mama
. I wouldn't be surprised if she had pretty tough separation anxiety right now, so I bet you're right about the vet Stim app't being tough on her.
As for when to Stim next -- you should be good for at least 6 mths, if not more. We watch for any change in symptoms (low or high cortisol) - and if there is, that's when we'd Stim again now that Wylie's med is stable.
Hope she is feeling better today and that her appetite is back!