I’m not sure that blaming tech support for not understanding context is the best approach here. The other sides of that context, which are understandable from their point of view, is that you were charged with some serious crimes. There’s a large delta between the charges and the conviction, but you’ve got some scary words written about you online. Secondarily, GitHub has policy so whereas you’re coming at it from a position of being correct, they’re in a position where they have to break policy. That’s a big risk.

Your best bet would likely be legal. US Federal law imposes some strict rules on lawyers for identity verification to combat money laundering so attorneys have a legally recognized toolkit to verify identity. Having a third party who works for you in the mix could help. Though again, it would involve breaking their policy so this would be a decision made several layers above Zendesk access.

Otherwise, I think this is doing precisely what 2FA is meant to do. It’s not okay for you and you’ve clearly lost a lot because of this, but with the current threat environment, GitHub has to be very careful especially with 2FA. From their point of view, there likely isn’t that big of a gap between your interactions and interactions with people who are trying to take over accounts. A lawyer may not work, but it sure changes that equation.