The whistle-blower in those conditions has a choice to make. He has a career and reputation to maintain and defend. He can act alone or he can act with the chain of command, which by training he is required to do. There are risks involved. It's hypothetical depending on the circumstances, but he certainly would need legal counsel.
Now, whether or not legal advice is successful in achieving his aim, in the process, being able to obtain some type of reimbursement for legal expenses spent by him is a different scenario.