Silkie chickens are probably the best option for sitting on quail eggs for a couple of different reasons: – they are smaller – they have amazing mothering instincts and want to sit on eggs
There is a good size difference between chickens, even bantam or silkie chickens, and quail, both full-grown and chicks.
Once the quail start to hatch, you should probably take them and brood them on your own.
Chickens and quail don't speak the same language and the quail won't go back to momma hen for warmth even when she calls them.
A few different things can happen to the baby quail if you leave them with the hen. – she may step on them – they may not get the warmth they need – baby quail need their food to be tiny or they can't eat it
You can definitely try to leave the babies under momma hen and see what happens. I'd recommend watching them closely