Ground pens are a great way to go, you just gotta remember to ocassionally worm them when you've got them on the ground, but the birds are definitely way happier that way. 

Whenever you introduce new quail, its best to put the new quail inside of a cage, inside of the of the big pen. Its best to leave them like that for atleast a week, if not 2 weeks so they can get used to each other.  Then just open the cage up and let them integrate on their own. And I wouldn't worry about seperating the special bird from the others unless you see some serious issues going on. I think you'll see that he gets around a whole lot better too once he gets to the ground as well. Add a coffee can or two, or some other type of smaller hiding spaces for the new quail to get inside of if they need to. There will be some pecking as they set their chain of command in place, so that will be normal. 

You can still get good results from still air incubators, so I wouldn't stress that part. Just try your best to get humidity around 55% 60%, and maintain steady temp at the topside of the eggs and all should go fine.