Communication is not always about bureaucratic bullshit, policies, sharing info that someone joined or left the company or other pleasant things. Sometimes it’s about problems!
How do you communicate when something critical for you business is happening?
In this case involve everybody into a message if you really think it is serious. Everybody must understand the impact and see clients reactions. And it’s all about only adding additional recepients into the email.
I would treat it a success if at least one person makes a conclusion and tries to avoid similar problems in the future or it encourages someone additional to help. And i don’t care if most treat it as spam, distraction or waste. If i really think it’s important - i don’t care.