I will be very disappointed if Miaq is not in the game
My theory of how he survived:
Miaq was trapped in an ice chunk for 200 years having to listen to everyone's conversations and complaint's who passed him. You come across him and melt him out with a torch, then he says in his awesome khajiit voice "Ohh thank you, you have no idea how long miaq has been trapped in that ice! Having to hear all of those idiots go on and on, it was driving me mad! He would then continue his random routine of randomly running around and telling random complaints of us