Focused, calm, but completely stubborn and ice cold "I can't leave until I have it documented why you aren't doing this" has worked for me. And warmth and trying to do social persuasion does not work imho with bigoted healthcare people. They have bully energy so you have to.
I made a couple example scripts to help my friends who were also facing challenging dismissal from doctors, not vax specific but may be useful as more people have to experience being denied reasonable healthcare for political reasons now.
https://www.drcathicks.com/post/talking-to-doctors-about-evidence-and-post-covid-symptoms
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