Um, they can spin that any way they want, but they were fading out to commercial anyways when star said, pretty clearly in a very sarcastic tone, "Joy you are still a bitch" which joy heard because you could see her and meredith react to it before the fadeout.
They sit next to each other a lot, they joke with each other a lot, they debate (In a very civil fashion unless it's about religion) a lot, etc...There's nothing to it. If they're fighting, they're the two best actresses on the planet when the camera is on...