The man lost more than his job, he lost his career. If there was no rule, written or otherwise, not even a precident of having two captains on deck while docking, the city is wrong in blaming him and destroying his name. I thought that the man was found guilty of negligence, however.
The city would still be right in blaming him. I am sure remaining conscious is an expectation if not a rule for the job. If it was a medical condition even more reason for him to lose this particluar job.