She did the right thing and it's unfortunate many folks here don't understand the reality of farm or ranch life.
Many years ago, we adopted a small dog from a no-kill shelter and we signed that if we had problems we would return him.
He bit my husband, snarled and growled at every male, almost bit my brother in law and went after my 4 year old nephew and I caught him just in time. I took him back to that shelter with a letter saying this dog bites and would especially be dangerous around small children. We told them verbally too.
We got a call a few months later asking if the bit anyone and that he had attacked several family members and a a child in his new family. I told them we made this clear and re-sent the original letter. He was euthanized after that I believe. It would have been better if we had taken care of things ourselves 🤷♀️
Anyway, I have had many inside dogs and livestock guardians and all are amazing and gentle. I likely wouldn’t have to have to shoot any dog attacking my chickens or goats because the pyrs would take care of them in short order, but I would shoot if I had to.