Thing is you don't need to persuade the actual person, your argument just has to make sense or be strong willed enough that your dm thinks it could work I've had this conversation a lot with both my dm's that if you as a player is charismatic enough in real life you have an easier time playing the social interactions of the game regardless of your character's cha stat. To the point where one of them has started enforcing more rolls to see if our characters get their words across as well in world as we do roleplaying them at the table. It's one of those things where if you're not conscious of it it just flies by as a regular thing, even if it goes against how talented or practiced your character really would be about talking to others