Took in a Grey that's been through a lot, advice?

So I volunteer at a animal santurary and about a month ago this African Grey came in. She had been in a car with her owners and other birds and they got into a car crash, her owners died along with all the other birds except her and she suffered no injuries. We were keeping her waiting for possible relatives to claim her, but no one ever did, so the santurary decided to keep her as a education bird. She and I bonded almost instantly, she would let me pick her up and feed her whIle she refused others to get near her. However as time went by she refused to eat anything but sunflower seeds and wouldn't allow anyone to handle her but me. She also began plucking her feathers, so since I did so well with her and I have a conure that I've had for years, the zoo asked if I wanted to take her in and I agreed, so I brought her home yesterday.

She is very sweet, but you can tell she's having a tough time. My biggest concern with her is eating and the plucking. At the zoo they were feeding her a seed diet, but she would mostly pick out the sunflower seeds. I saw her drink water once since I brought her home, but she refuses to eat. I put the pellets I feed my conure in her bowl, along with nutriberries, some bird popcorn and orange slices. She won't touch any of it, she picked up a few things and just throws them on the floor. Now at the zoo a few times I would eat lunch with her and I got her to eat a few things, but she had to be on my shoulder and I had to hand feed her. I don't want to start bad habits, so Im avoiding doing this at home, but I don't want her to starve. My conure picked up on eating pellets very quickly, but I already know she's going to be very stubborn about this.

I put some bird vitamins in her water, I have them for my conure because he can at times be a picky eater and I always worry about him not getting enough nutrients. She's plucking a little, but I'm guessing that is something that overtime she may stop once she gets comfortable in her new surroundings? She also bites at the cage a lot, but again I'm guessing this is just a stress thing she's doing for being in a new environment.

Any advice, food/plucking related or otherwise would be greatly apperciated. I just want to make sure I'm doing all I can and exploring all options to help get her back in a good place mentally and physically.

I named her Daenerys : ) She is very gentle and loves me picking her up. She can whistle, bark like a dog and sing do, rei, me. I have no idea if she actually is male or female (she felt female to me lol) or even her age, when she was brought to the zoo we were given no information on her at all.

Welcome and I'm sorry to hear that such a sad event occurred to bring you together. My GCA Buddy came to live with us about a year ago after both his owners had passed away. We've been told Buddy has a big vocabulary but he will say "hello", "wow" and blow kisses. He does closet talk meaning he'll be alone in the room and start talking in a low voice. We enter the room and he gets silent. He's not the same from what people describe in his past.

I spent most meals with him, he eats when we eat. I sit close to his cage so I will put fresh food in his bowl when we dine. He thinks he's eating the same and eats most things. I didn't give him seed at all. The winning foods in the beginning were scrambled eggs, blueberries, pear, and red pepper. Keep offering food but you might have to keep feeding and eating as a flock. Try a perch at the dinner table and give him a bowl or plate of food. For Venus, Buddy and Venus love warm brown rice with veggies like purple hull peas, okra, corn, peppers, broccoli etc. last night I gave them fresh pineapple and they slung it out. Stinkers, it was delicious pineapple too. Keep doing what you are doing and maybe those are some ideas you can try. Keep up the good work!