I wouldn’t try stuffing anything in her beak. Wet her crumbles into a mash. Give her some time to investigate the mash with added egg and/or chicken. Remember she is in a strange place the past few days away from her flock and probably in a lot of pain, it wouldn’t be abnormal to not have much of an appetite. Another idea is to take her near her flock for a short, supervised visit and try to feed her there. I’ve heard of chickens having much improved appetite after visiting with their flock. But if you choose to try this, don’t leave her out there unattended. You’ll have to watch that she doesn’t get attacked by others and that no flies land on her injury.I gave her crumbles. Should I try stuffing it in her beak yet, or wait to see if she'll peck at it with the added ingredients?
Is her injury showing any signs of infection?