I think my idea for trying to get Lily to just stick to one box is put fake eggs in the one you think she'd like the best and see if she'd plant herself to that one instead of going to every nest like she's doing. You could try it a couple of different ways to experiment. Maybe in time she'll...
It wouldn't be the first time I heard a broody hen passed away. I'm sorry for your loss. :hugs
As for Lily, she may be trying to be broody and is following the other hen around to be able to sit on her egg. In a breeder pen, we have two nests for 5 hens, and they almost always lay in...