Greetings
Mom3timz,
Don't worry about this incident. Instead, do as
peckpeckpeck suggested. Place some fake eggs in all of the nest boxes. Be sure to put some little marks on the fake eggs, so you don't accidentally collect them, too. Sometimes an egg breaks when a hen is trying to move it with their beak, or it can get cracked when the hen steps on it.
Hens also, get very upset when the nest is soiled by egg contents. When they try to tidy up, they taste the egg and discover it's edible. But, it's the hen that purposely waits for others to lay an egg and then goes into the nest box to break the egg and eat it, that has to be dealt with.
Thankfully, I have never had to deal with a hen for egg eating. Immediate clean up of the nest box in necessary. You don't want this to become a learned behavior by leaving the mess.
I also find that adding some curtains to the nest boxes, helps the hens to feel safer while laying their egg.
These are my thoughts on your egg issue, I hope they are helpful.
God Bless and peace to you.