Janet, I would try to separate them & put each of them into their own secure space with their own eggs if possible.  If the eggs are a mixed bunch from all your hens I would choose the smallest ones for the game bird & leave the larger ones for the big girl.  One thing to remember is that game birds have a reputation for not making good mothers. I have no experience of them.

I have had 2 or 3 hens go broody together in the past but this has always resulted in chaos, broken eggs plus fighting & jealousy at hatching time. I always try to keep any broody & her eggs shut away from other hens as otherwise you can suddenly find all your hens will suddenly get the urge to join her & your egg supply will stop completely.

Good luck.  

Hi Janet,

This afternoon take a shallow seed tray filled with wood-shavings or straw & make a little shallow nest  in it for all the eggs & let her climb back on them & settle down. Leave her till it is dark & then cover her with a light piece of cloth (I use an large old dark silk scarf; being in the dark keeps them calm). Carry her to the new home which you have previously prepared with new bedding which is similar to the stuff in the seed tray (my maternity home is an ancient rabbit hutch). Just place the eggs in the tray with her on top straight into the new home, don't take the eggs out of the tray till the next day by which time she should be totally used to the new surroundings.

This is just the way I have developed over the years.....it works for me most of the time but if you have a really jumpy hen you may have to try it a couple of times.

It doesn't surprise me that your game hen gave up....she probably would have done that at some time later, even if the big girl hadn't taken over. 

Good luck