From what I can see it seems you have a female on your hands that is getting her adult feathers. Most female yellow golden pheasants tend to get darker as they get their adult plumage. Is her eye yellowish green or dark brown? I have attached a picture of an adult female
She looks like a juvenile Yellow Golden hen to me. She might get darker as she matures. Here's a couple of pics of 2 of mine. They are going through a molt right now.