No!! The co-workers could have figured it out. It only takes one to find out and spread the word. Even if they did find out the supervisors should not be teasing him as they are creating a hostile work place.
The other attorneys are correct that the information should have remained confidential, but it may also just be process of elimination in terms of how people found out. Your husband would have an exceptionally difficult time proving who and how it was released and might be better served just focusing on getting back on track with his employer.
Each employment situation has unique facts and circumstances. This means that information and advice cannot be taken literally and should be used as only informational. The information provided here is not legal advice and should not be interpreted as such.