I feel really bad to have to tell you this... all 4 of those with black feathers on their chests are cockerels. Sometimes male SGD chicks will have a dark triangle on their head like a female. It's not a 100% way to sex them. The black feathers on the breast tell you they are male. Salmon (reddish brown) breast feathers are pullets (female).
The very light one on the end is one of her made up colors. Unless White chicks look like that? Not sure on the next one, maybe Red? Third one may be Red. The lightish marked ones may be male SG or mixed color. The two with the dark triangles look colored like your McMurray SGs, don't they?
Even if they feather out looking like a standard color, if they are mixed with another variety, they may not breed true.
You may possibly have a SG trio if those two are SG pullets, you could try breeding them to the McM male and see what you get. I hope that you get some pullets from the McM batch.
Where are you located?
To answer your question about raising the poult, some people do raise turkeys with chickens. I did. Chickens sometimes carry Blackhead, which will kill turkeys. So that's a risk. And turkeys need higher protein food than chickens. You might ask about this on a turkey thread.