Why isnt "Ni yeye mpishi?" Accepted
Because that's English word order, not Swahili word order. In Swahili, to ask this question, you can indicate it with intonation alone (a question mark in writing) or with "Je, ... ?" You don't put the verb at the beginning to indicate a question.
So then why is "Je, yeye ni mpishi?" not accepted?
it is now!
Why not "Je yeye ni mpishi?"