The break given by Ambassador Abores allowed Khan to relax and focus on his situation. He didn't only have Mister Cirvags' offer to consider. The conversation with Monica had also opened a new path that required tests.
The first issue was easy to clear once Khan took the time to consider it properly. Mister Cirvags' offer would split him from Ambassador Abores, solving the internal conflict caused by Neuria's events.
Moreover, the mission in Cegnore involved Khan's main goal. It could bring new leads on his search for the Nak. Even if Mister Cirvags was untrustworthy, Khan couldn't ignore that opportunity.
Accepting Mister Cirvags' offer pushed Khan's thoughts to the next problem. Cegnore was a battlefield that the Thilku struggled to dominate. He needed to get stronger to affect that environment.