You didn't really make sense^^ The village wasn't in anarchy, they still had control of the situation and had they attack then they would be facing Jiraiya, Gai, Asuma, Kurenai, Kakashi, the Hyuuga clan, Nara clan, Choji clan, Ino clan, Kiba clan, Shino clan, Anbu black opts, the jounins, and the Chunins which is too much of Itachi and Kisame to handle. Itachi had no knowledge Jiraiya was Hokage candidate, no one knew but the 2 elders (3 if you count Danzo) and a Jiraiya himself. How is that logic of Kisame not trusting Itachi wrong? That's actual manga fact of the flashback and this is a organization od S rank criminals, you really think they're going to really trust each other? Kisame respected Itachi but trust is another thing, he did kill his comrades in his flashback as well and Itachi knows this since Kisame brought it up as well as a Itachi killing his clan which made them good to be partners with.