Ok, the broody situation is getting out of hand

I have EIGHT hens thinking they need babies! Those are just the commuted ones too… A few have sat for a few days and decided it was not for them. My silkies and banty Cochin have been given eggs, but I’m not sure if it was a good idea. They’d been sitting for at least a week and the eggs were fresh. So several ideas I need help with!
1. Let them keep sitting on the eggs
1a. Put in incubator if they don’t last the whole 21 days
2. Prefab coop as Broodyland: Move Ethel the Polish who prefers solitude and put all my broodies in that coop. Slip chicks under them in the night (fresh hatched Marans)
3. Try to fit the popup crate in the main coop. Who do I pick up go in? Can several hens share it?