According to LeBatard's article, there is no proof that a crime was comimtted. No proof that guns were drawn. They can't confirm that the original story is true. All they know for sure is that both players keep guns in their lockers, and considering how two NBA players were recently robbed at gunpoint, that's understandable.
Yet by the rules they should have both been suspended for having weapons on the grounds, yet only one is punished. Arenas was right to make fun about it as the whole policy is a joke with no enforcement.