User blog comment:Spritydove/Deeper Thought into the Civil War/@comment-5135631-20120707164216/@comment-5229167-20120713032254

The dossier labels him as a Thalmor asset, but points out that he isn't very cooperative. This is further reinforced by the fact that the Thalmor were at Helgen when Ulfric was scheduled to be executed. They surely would have intervened to prolong the civil war if the dragon hadn't attacked.