I would love to be able to say what type of Quail this is,but seeing as it was an un-known hybrid from a private collection that kept atleast,4 species of Quail in the same aviary I don't think will be able to.
You are correct, it has been confirmed that this bird IS a hybrid Bobwhite X Californian Quail.
There were two kept in 2012 and at least one of these died at Paultons.