First - You should get a compatibility chart and review which fish are compatible with each other - Just Google it.
Second - in most cases I would not mix Mbuna with Haps, especially Johanni they are particularly aggressive.
Third - it is not recommended to have two males of the same species in the same tank. the sub-dominant male will most likely color down.
Regarding the not eating, I would recommend putting in several hiding spots, rocks, decor, etc..
What size tank are these fish in ?