@ I mean the whole university was like non Somali students.
Is that how you come to your conclusion Garissa is 50% bantus?
First of all the reason why they were majority there is, it's cheap, second it's not a prestigious university, third the college specializes in teaching courses mostly ( it was a former nep teachers college later renamed Garissa university) Thirdly there are as much Somali university students from where the Bantus came from as there are lots of Bantus students in Garissa. Forthly in Kenya, doctors, the army, police etc etc are all transferred all over the country once qualified or trained irrespective of the persons background. You will find Somali nurses, doctors, army personnel, police scattered all over the country the same way what you call "Bantus" (a collection of various tribes) are found living & working in Garissa. Lastly, Somalis who qualify for Uni seek more lucrative courses offered in Nairobi universities than joining the Garissa one which caters mainly for students doing teaching courses.
The rest Not worth a reply. Salaama ka dheh duqa