Rondo's playing horribly in Dallas, I'm not sure why it's so hard for you to accept that. No one's saying Dirk isn't having a disappointing season, but Dirk's the franchise cornerstone, not the new guy whom people are evaluating to see how he fits with this team going forward.
He's also not getting into a public shouting match with Carlisle. Dirk's struggles are independent of what just happened with Rondo. As soon as Dirk starts cursing out Rick in public, then you might have a point. Until then, you're just kinda desperately grasping at strawmen in defense of Rondo for some reason. He's been struggling, he messed up, and was out of line by doing what he did. It is what it is. Rondo's not above reproach.