Even if it's working now with them together I wouldn't make long term plans for it staying that way. To many bad experiences with size difference like that. especially some, not all, male quail can be quite mean and territorial. So they may start the problem at maturity but not be able to finish it.
Just because of the size difference I personally wouldn't keep them together. I have orpingtons and Plymouth Rock. My mom originally gave me silkies. when I added the bigger girls as pullets to the flock of little bantams it was not good. Well it started good and ended bad. I ended up having two...