Talk:Imperial Raider Expansion Pack/@comment-150.204.17.245-20150318143356/@comment-150.204.17.245-20150319094526

"Although Thrawn did not become a high-ranking officer before the Battle of Yavin, [12]  he began the exploration of the Unknown Regions early in his career. [17]  "

(source:  http://starwars.wikia.com/wiki/Mitth%27raw%27nuruodo)

So he would be a low rank if he were there and, as you said, he makes more sense than palpy or tarkin - Mon mothma isn't there for the rebels after all.