The Excellencies' approving nods updated Khan on an annoying truth. The additional term had become mandatory, and Khan couldn't talk his way out of it. Either he accepted the deal, or the war would start.
The idea of returning to Baoway with an evolved warrior could bring many benefits. Knowledge of that higher realm was one of the key flaws of Khan's procedure. The help of someone who had already faced and overcome a similar hurdle would be priceless, but Khan's paranoia blinded him, forcing him to focus on the potential dangers.
Khan was confident in his strength, but a battle against an evolved soldier remained a scary prospect. He wouldn't bother with those meetings otherwise, and the deal involved bringing such a dangerous figure into his home.