Khan wasn't at his peak. Even the rest from the previous day couldn't fix the overall tiredness that filled his body. Yet, he had fought in worse conditions.
Maban continued to express his pressure and coldness, but he eventually performed a slight nod. That reaction confirmed Khan's guess. Maban wanted to test him out, which was reasonable considering the situation.
The recording from the club didn't show Khan's battle. He could have made a secret deal with the Orlats as far as Maban knew. Sure, the matter sounded unlikely since the third-level warrior had died, but Maban had to go over all his doubts before accepting Khan completely.
Khan knew how the Nele fought, so his entire attention went on the symphony of mana. He didn't care about sensing everything Maban did, but he wanted to reach a mental state that could trigger automatic reactions.