This year I had a goose setting. Something got her eggs as well. I brought 5 babies. I didn't give them to her for fear of what Lydia said. But when she hears them she runs near their pen.
I believe the foxes are coming out in daylight because they have kits to feed. I'm not excusing their behavior and I'm truly sorry about your hen. I hope she gets better.
Further more when you had them free ranging and then locked them up, you probably shocked their system so it threw them off. I know because i did that one year. Big mistake.
At this point you don't need any artificial light. My muscovies are laying and my coworker has 2 that have started setting in the barn and in the rosebush.
Well my muscovies made their own nest where the wanted to. When I had my pekins and mallards they laid on the edge of the pond. Sometimes too close and they would roll into the water.