Yes,an accidental shooting is a real possibility.
However,just a short tale that might be worth considering:
A few years ago we went to Kenya to see some game parks.The guide we had for the several days we were there was named James and was an native African/Kenyan (IOW he wasn't white).During the long drives we had between Nairobi and the parks James and I would talk about politics and society.We got onto the topic of economic development in Kenya and for a while he focused on crime being a negative factor.He specifically talked at some length about how Somalians living illegally in Kenya were responsible for the huge majority of violent crimes in Nairobi,as well as that famous (and incredibly brutal) terrorist attack in Nairobi a few years earlier.
He also mentioned that there's a huge portion of Kenyan territory near the Somali border where sane people dare not go for fear of being kidnapped...or killed...by Somalis.
This certainly could have been an accident.It also could have been a huge error in judgment.But remember all the Coalition troops who been murdered by "friendly" Afghans and Iraqis (IOW,a lone wolf jihadi).
I am wondering whether the sexual assault was perpetrated by another member of the Moslim tribe. That would change things.
Interesting, but I know of one hair-raising story involving a seemingly civilized Kenyan. This was during WWII. The story is in Roald Dahl’s book “Going Solo,” about his experiences serving in the RAF in Africa and Greece during the war.