Speaking about Kanki, I have been wondering if Kanki might have some men inside the city in the same way Ousen did.
The easiest way for the city to fall would be if a riot starts which is what Riboku and Earl Ki fear most.
Riboku expects that Earl Ki can keep the situation under control for another two days.
However, if Kanki has some of his bandits disguised as Zhao soldiers then they can start a mass riot by spreading info about the food situation and by killing a few civilians.
Once that happens, Kanki can kick back and laugh his arse off.