You are both illogical.
In ODM-UDA camp, ODM is likely to get Nairobi. Sakaja is a UDA member and his deal died with Raila. Babu Owino has a much better chance of getting the ticket now. If Sakaja decides to run as UDA the Broad-Based vote will split.
On opposition side the math remains the same. The colorless Gakuya likely to get the joint ticket and win purely on tribe.
The idea that Nairobians will suddenly mature and vote for "Dishi na County" is wishful thinking. On what basis did Sakaja beat Igathe?

Now, Babu Owino vs Gakuya should be interesting. My money is on Babu. Unless Sakaja plays the spoiler.