Speculation aside - he needed to improve his personal security years ago. When he hobnob with those big guys - he should notice most of them are under 24hours security - because you step on many toes.
For now until election - 2021 - I would advice Itumbi and my guy Chirchir - to have as good security as Biwott had. Be mysterious. Dont use the same car. It's better to jump into ubers and taxis. Dont live in same house for two days. Have 20 phones....and keep them in 20 seperate places...because they will be tracking that phone.
The same thing for Ruto - double down on security - double down on counter intelligence. Hire private security to complement - and hire more informers - or bribe more for information.
If you are going to take power against hostile gov - it's will take more than the usual. The next six months - the Matiangis and his Harambee hse crew will get even more desperate because they know power is going and some of them could be in prison - so expect very stupid and desperate moves.
Itumbi is crucial part of Ruto online propaganda - and therefore Ruto should simply adopt him for six months - he can stay in SQ in Karen
This may be more of an inside job. Itumbi should secure body guards. Someone close to him is after him