The naked neck is the one I suspected first... Those are some BIG wattles for a 6 month old hen, but I don't see any saddle feathers so perhaps not.
I also notice the Show Girl/Naked Neck Mix seems red in the face, but her body looks like a hen.
A silkie is a possibility but they all look like pullets to me.
So I'm stumped! I will keep staring that the pictures some more. I would bundle up with some hot coffee and spend a couple hours out there with them and wait for someone to get busy, if it were me. I'd have to know!
MAAAABYE.. see these: 2 Japanese Bantam, Hatched May 1, 2013 ?
See how one is larger and has red feathers in the neck? Can you take more pictures of that one, side shots? the face looks like a girl but just curious.