Hugo's relationship with the gods was not a close one. Those who could know that Annan was the Celestial Chariot were generally True Gods, False Gods, or those directly related to the deities.
Even the gods could not know things that had nothing to do with them. Their grasp of information about Annan was linked to the previous cycle when "Black Annan" had connections with the True Gods.
Logically speaking, Tower Master Hugo should not have known that Annan was the Celestial Chariot.
But Annan quickly realized... It must have been Bernardino who told Hugo. Their relationship did not seem to be entirely adversarial.
Just as Annan had explained to Thirteen Fragrances before—the friendships of young wizards were primarily built around "talent." Because if the gap in talent was too wide, after graduation, there would essentially be no intersection in their lives.
Considering Hugo and Bernardino both eventually became Wizards of the Gold rank and their ages were not much different.
