"Patel...is deeply concerned that his job is in jeopardy."
This should be true regardless of his drinking and behavior. In Trump's five years, his administrations have had massive turnover, and he continues to live up to the his famous catch phrase: "You're fired!" I can't see how someone wouldn't understand this when they take the job.
Dude wasn't jaded enough to know what he was getting into, the sort of evil he'd be running cover for, when he took the job. Yeah I'd drink a lot and be paranoid too.