Shortly after the battle of Yavin, Thillis took part in a negotiation with Yeeru Chivkyrie, Ydor Vokkoli and Princess Leia Organa. There, Chivkyrie presented a plan that could give the rebellion a great boost, which he and his colleague Vokkoli had, however, something and threatened with an exit from the Rebellion. The plan included a declaration of independence from the Shelsha sector against the Empire, with Chivkyrie not knowing the exact plan but only Vilim Disra and Barshnis Choard. For this alone, Thillis had doubts as to whether these would be loyal to Alliance. Finally, to get the exact plan, they flew to meet Vilim Disra on Shelkonwa. This, however, quickly betrayed them to the Empire, so they had to hide. He fled with his colleague Vokkoli, leaving his friend Chivkyrie reluctantly to return to Shelkonwa with Leia Organa.