They will not cross breed,but I would be concerned in adding a hen to an established pen.Plus come breeding season,the males will fight.Their breeding season starts in Feb.I would cut your pen in 2 and have a seperate pen for each species.They can be housed with peafowl.
If at all possible,I would get the temminick hen as soon as possible,so she will be settled in before she starts to lay.Sometimes moving them during laying season slows and sometimes stops their laying.
I use bushel baskets for nesting boxes,both hanging and on the ground,a piece of plywood leaning on the side of their pen,and an mas tree leaning in the corner.This gives them options for where they feel comfortable as to where to lay their eggs.I also have some wooden apple boes hanging from the side of their pen,but they don't seem to use them as much as the bushel baskets.
In N.H.,Tony.