When you say “new rules,” are you referring to this? Actions Taken to Curb Griefing by Repeatedly Leaving Groups
If so, that’s a very specific thing that doesn’t apply to your situation. Even if it did, there would be no report for you to make, because it’s based on people being frequent offenders, which you can’t know - Blizzard monitors and takes action as they find appropriate.
If that’s not what you mean, then I don’t know what you do mean, as there aren’t any new rules. I can’t add to what’s already been said.