I don't think current skirmishes has eroded Ruto ability to attract people to his camp. You have to understand that everyone who has supported Raila is very weary after loss n loss n loss. You can check Kichwa or Patel here. They are DONE. The worst Raila did was to boycott the repeat election. So Ruto is the only hope. Raila the magician has to first work his magic otherwise he has exhausted the goodwill he had from his supporters. You cannot support who chicken out of a repeat election, swear himself and then capitulate in a handshake that does not make sense.
The other big elephant - nobody really knows what Kenyatta is up-to. He is just playing all sides. He has kept his cards very close to his chest.
As for Kiunjuri - I think you underrate him at your own peril. The rout you saw in Central was engineered by Kiunjuri. Yes he doesn't speak fluent English but he is very deadly in Kikuyu. He is also an experienced political operator with about 20yrs in the dungeons. I think he became MP with Ruto in 1997 - about 22yrs ago - as 30yrs old.Wa-iria and Kuria are just jokers - with less than 10yrs in politics. Kuria from Gatundu south is dead on arrival - a joker who is not even 5yrs old in parliament. He cannot get even A SINGLE MP to support him. Wa Iria is also about 6yrs in politics and cannot get ONE SINGLE MP to support his bid. They are just about as worse as Nancy-Kibicho when it comes to politics.
Waiguru is good on Camera but he has to deal with iron ladies of Kirinyanga - and she is struggling there - Kirinyanga hopsital in shambles. Ngilu and Joyce are doing womenfolk great in Bomet & Kitui.
In short - like I told you in 2016 - watch KIUNJURI very closely. Already he has Kikuyu diaspora in Nakuru, Uasin Gishu and Laikipia. Those are united in RUto camp. They do not want to become the PAWNS in a reckless game of Kibicho-Nancy. They want the current peace with Kalenjin to last.
So Kiunjuri starts with 1M plus Kikuyus in diaspora. He also has very deep roots in Nyeri & Kirinyanga. He will struggle in Muranga and Kiambu - and that is where Uhuru can make or break him.
To nick Meru & mt Kenya east - Kiunjuri has to make a deal with Kiraitu & Muturi - because of Munya like all those who lost in 2017 blames Ruto & Kiunjuri for their misfortunes.
Anyway I reckon things are becoming clearer n clearer as we heads toward 2022.
The trouble with your observation - is that Mt Kenya succession or Jubilee wrangles do not exist in isolation to the rest of Kenya. For instance folks who want to join Ruto would simply be joining Jubilee, but it not clear now if Jubilee will even exist by 2022. Or if Ruto can manage to wrest it from Uhuru boys. If you're Khalwale or Kingi - which party do you decamp to - to back Ruto? You're basically partyless clinging to Ruto.
Two, only Jubilee outside of Mt Kenya is behind Ruto. This is basically URP. The rest are two-three Nanok or Khalwale or Jumwa. Jubilee had mere 53% even with 99% Gema and incumbency. Luhya, Mijikenda, Gusii, Kamba - these are very hard nuts to crack for Ruto. They all supported Babu before - and right now support Handshake. Babu just needs to maintain that coalition while instigating Jubilee civil war.
This scenario makes referendum very critical. Cause disruptive realignments. It why BBI lever is a big deal - and why it risky for Ruto to oppose inclusion. Of course you underrate Moses Kuria - while overrating loser Kiunjuri. I'm yet to be convinced of Kiunjuri brilliance or leadership. Anyway, Kiunjuri is in a tight spot - in the Jubilee skirmishes - cause wa Iria or Kuria with Uhuru support can be tough to deal with.