@KuJoe One approach I've often found to work, is to individually ask each of them "so your point is that _______?", where on the blank goes a very specific phrasing that a) makes the misunderstanding easy to implicitly pick out for the other person, and b) is similar for the "clarification" question to both parties, so that it becomes obvious to both that they're actually very similar points.
@joepie91 This is a really good idea and I'll definitely try that next time.
What's funny though is in the argument that prompted my post, I read further down and one of them pointed out that the thing they were fighting over was different and they both were actually agreeing with each other but then it devolved into personal attacks after that. 🤣