Does this girl have a right to trash the foundation?

A friend of mine got a dog of Craigslist who ended up having extremely high anxiety. Due to her work schedule and inexperience, she decided to surrender the dog after the dog started to hurt himself while she was away. She gave a very thorough report to the foundation she surrendered the dog to about his anxiety and also not being able to be around other dogs. She called a few days later to see how he was doing and she found out they euthanized the poor dog after they put him in a kennel with another dog and there was and incident. My friend has now started a pretty heavy smear campaign (I think that’s the right term) against this foundation. Telling her story and begging everyone to share it on social media, leave bad reviews, and reach out to tell them how horrible they are and quit a few of her friends have posted screenshots of them messaging the place and chewing them out. She is posting multiple times daily about how much she misses her dog and wants the foundation to be shut down for not listening to her instructions. (I do feel sorry for her but, I feel like it’s getting to the excessive side.)

Let me start off by saying that what happened to this poor dog is so horrible and sad. And the staff was uncaring and/or ridiculously stupid. That being said, I had to surrender a dog a one point in my life and I did tons of research making sure that wherever I took him had a good reputation and was NO KILL shelter. The website of this place clearly states that they are NOT a no kill shelter. Now, I’m not asking if we should have or have not kill shelters. I’m asking if this girl has the right to try to trash and get her friends to trash the organization to the extent that she is when she didn’t do thorough research. Do pet owners have a responsibility to know where they are giving their pet away to?