She is a cutie!! Try not to have her so covered all the time, better bright light can increase activity and eating.
The soft fuzzy hut beds..it's easy for them to pull off and injest that fuzz. I do use sleep tents for mine , but I get the more fabric , canvas , low fuzz ones. You can test any buy pulling with your fingers if threads and fuzz vine right off it's bad . Thst builds up in their crop , and over time s lot gets stuck in their sbd can even impact the crop. Any soft ropes that you can pull thread off are the worst too .
I use zoo preem as one of my pellets in rotation too. But I think something is missing from this pellet or formula. 2 of my quakers came to me eating zoo preem only , both were under weight , with less than ideal feathers ..I have noticed this with others as well. I can't give you facts , but I strongly feel the formula is off , to low of essential fatty acids or they aren't adorable fir dime reason..
When I changed my quaker girls and got them eating other pellet brands and vegg they gained back weight quickly and feathers improved to ideal lushness. They had no health issues, it was just the diet.
Don't give up on veggies! I took in a near 20 year old seed eater only Quaker and got her eating healthy it took time! I really wanted her eating leafy greens, it took 2 years for that to happen. And I kid you not they become in her top 3 favorite veg and she ate daily!!!! After resistance for 2 years!!!
You can try a minced up veggies and different pellets pre soaked and crumble into an omelette and try that. I hid them in everything st first like mizzly mentioned above in bird muffins, the omelet , Ive also had luck steaming and mix in cooked quinoa served warm . Mine love cooked sweet potato mash , and I dampen and crumble pellets in that as well .