Hello and welcome to y! Glad you joined.
Sorry about Molly.
I've had excellent success containing my flock within poultry netting powered with a 10,000 volt charger. They also have lots of thick shrub cover and 3 roosters on lookout duty.
Welcome to BYC - sorry for your loss. For now a solid pen with hot wire protection and monitored free ranging until you can figure out/control the predator. It will return.
So sorry for your loss. I would build them a nice secure pen. Now your birds have been discovered and the predator will be back. There are ways to entertain the birds. I also have game cameras up and was surprised at the predators that roam here. Good luck and have fun...