what platform do you play oblivion on?
He's playing on the "trolling with false information" platform.
There is loads of information about Skyrim
the province in previous Elder Scrolls games, and of course all manner of talk about dragons. I wouldn't call this "hints" though, simply the lore of the world.
Alduin is actually the Nordic version of Akatosh, and Akatosh is the central deity and symbol of the empire, so actually, you could say all those dragon symbols used to represent the empire in Morrowind and Oblivion (and on the cover of Morrowind) depict Alduin. Though those dragon symbols may also represent Akavir, it's a little ambiguous really.
From the book
Varieties of Faith the the EmpireAkatosh (Dragon God of Time): Akatosh is the chief deity of the Nine Divines (the major religious cult of Cyrodiil and its provinces), and one of two deities found in every Tamrielic religion (the other is Lorkhan). He is generally considered to be the first of the Gods to form in the Beginning Place; after his establishment, other spirits found the process of being easier and the various pantheons of the world emerged. He is the ultimate God of the Cyrodilic Empire, where he embodies the qualities of endurance, invincibility, and everlasting legitimacy.
Alduin (World Eater): Alduin is the Nordic variation of Akatosh, and only superficially resembles his counterpart in the Nine Divines. For example, Alduin's sobriquet, 'the world eater', comes from myths that depict him as the horrible, rauaging firestorm that destroyed the last world to begin this one. Nords therefore see the god of time as both creator and harbinger of the apocalypse. He is not the chief of the Nordic pantheon (in fact, that pantheon has no chief; see Shor, below) but its wellspring, albeit a grim and frightening one.