Are you sure? I thought "The Dragonborn comes" was all in English. The lyrics to the parts I've heard certainly don't match any part of the main theme.
No, you're right, BUT the first half is The Dragonborn Comes, the second half is the main theme (in Dragon)
Incredible job, and yes, I would like to see this modded into the game also.
Someone already did (look a few posts up, I posted a link).