From what i've read on the even generations (2, 4, 6 and so on) if you take good care and feed your tama sushi and apples your likely to get a mimitchi (yes, i did read that here also but i learned that from tamatalk a few months ago and it does work!)
I got Mimitchi with that diet and proper care/exercise in Gen4 in V3 even when her behavior bar was only 6 out of 10.