They wanted her to pay a bribe. Kenyans are hard for Ethiopians when they want them to pay a bribe. If she was a Somali, they would've easily asked her to give them some money. But Kenyans learned Ethiopians don't give up money so easily, so they make their life hell in Kenya when they want them to pay a bribe.
Kenyan govt should pay their employees well so they don't solicit money from African passengers and make the life of African travelers hell.