I would encourage your husband to consult in person with an employment lawyer. He may have a valid whistle blower claim.
My answers to questions posted on AVVO are intended to provide general information only, and are not intended to be legal advice. Employment law issues typically require a careful case-by-case analysis. Consequently, if you feel that you need legal advice, I would encourage you to consult in person with an employment attorney in your area.
You husband should definitely consult with an employment attorney. In addition to the whistleblower claim, it's possible he has a worker's compensation retaliation claim. But both claims are very fact intensive and would require an interview.