I have never seen Cinnies or Black pastels throw out those babies.

I've never seen that particular trait happen at all.. Looks like the cleft palate in humans.

In the super form of Black Pastel/Cinny, they have a "duck bill", as in the face is flatter and wider, but not like that...

Maybe someone with more experience with that can chime in, but in my personal experience, I have never had any babies like that.