We'll know if it's right when they "release the comic that explains it" in October. Although the leak doesn't make sense at some points like when he's describing the Stormwind Raid.
He says the first bit is a caravan/battering ram bit with goblin/gnomes means H/A working together.
Then next bit is dealing with some Old God baddies because they're trying to get us to stop reaching Sylvanas??? Despite the Void seeing her as an enemy?
All of the Horde leaders rejoin Sylvanas? Because out of nowhere unexplained and abruptly the Lich King is now on the Alliance side, what?
Then we're all supposed to die to be ready for the "true Battle of Azeroth" which is what even? If the Old Gods are aiding Sylvanas during the SW raid then who's the actual enemy in the end if not Old Gods?