I would have no problem sourcing an IG from the Commonwealth for a one term contract. Preferably Mzungu. Yes, Moon Ki you heard me! Mzungu. I would give him instructions to clean up the mess. 
And why would I have any problems with that?   I don't.   I have seen such people brought in by some other Commonwealth countries, and, for the most part, it seems to have worked quite well.   Such a person does not have his "our people" to take care of (at the taxpayer's expense) has not developed a taste for  "chicken", and, being far from home, has little to occupy him/her other than work.   
Even if Kenya insists on having a 
kienyeji IG, the rot in the police force is now so deeply set that a major change will come about only through extensive re-training by outside elements.   But I don't see that happening.
To the extent that I have an issue with the "mzungu" element, it is that I think folks from, say, Singapore, could do an excellent job.
But at the end of the day, my position on many such things always boils down to this: the average Kenyan needs to get serious and change.   The unpleasant fact is that many Kenyans actually accept tribalism and corruption; they get worked up only when someone else is benefiting.