Canon, that is, until Blizzard demotes the Chronicle book as "well it was just from a/an <insert in-universe POV>, not actually a meta lore bible".Don't waste your $$ on this; you'll just come to regret it later.
Wonder why CoS is Ally? You'd figure at least Horde, or maybe both.
I'm not gonna dig too dip into the cesspool this discussion turned into, but
Incredible
Uldir is stupid. Should be a Horde clear.