I agree there are two use cases. I arrived at a slightly different solution.
The first use case is what you get for free from Facebook’s terms of service. Twitter can resolve this by demoting verification from a badge to information.
For example “verified” text or “disputed” text by a name.
The second use case can either be punted for fear of the volitivity (an otherwise notable person reveals their horrible characteristics, see PewDiePie) or bias towards a badging system similar to Yelp.
I’d probably bias toward deprioritizing making the second use case visible, and instead, use it as a factor in ranking and promoting in the twitter feed under the hypothesis that great content should be its own promotion.