Don't give her wormer unless she has worms. Vit d would be good though.
How long have you kept her in the garage? It sounds like lack of sunlight may be an issue. Without it, she can't make vit d, and without vit d she can't metabolize calcium properly. Though that doesn't matter for grit and undigested food.
I would reintroduce her to the flock and see if she's stopped the pecking behaviour.
How long have you kept her in the garage? It sounds like lack of sunlight may be an issue. Without it, she can't make vit d, and without vit d she can't metabolize calcium properly. Though that doesn't matter for grit and undigested food.
I would reintroduce her to the flock and see if she's stopped the pecking behaviour.