I don't believe you are remembering correctly BobbieCD, although possibly your memory is combining two separate incidents. Sammi was remembering Chaka sparing with the protagonist of the story, and Chaka was the protagonist in the fight with Montana, which is where she suffered the from the cheap shot while her back was turned. However, since Montana is from Twain and is not, despite his fur, a werewolf, you might be on the right track with the rest of your description.

To Sammi, I think it may be a non-canon story because I don't recall any canon stories with the exact mix you describe. More specifically, I don't remember any canon stories where the viewpoint character loses their temper with Chaka during a sparing match. Outside of sparing, yes ;) and people seeing others lose their tempers in the ring, yes. But not the combination you mention.

Edit: Although, I personally don't care for the writing styles of Elrod or E.E.Nalley, so there is that noticeable chunk of canon that I am unfamiliar with.