I have no knowledge if what I am about to say had any impact whatsoever on the accident under discussion, however...
I feel an employer should indeed have the ultimate right to hire and fire employees. There are rules to protect individuals from unscrupulous employers. They protect pilots in just the same way anyone else is protected.
It is perfectly correct to say that the most important tool in any pilot's (not just captain's!) armoury, is the ability to say 'no'. The innate sense of self preservation must never come second to any other consideration. Ever.
However, in the field of corporate/private operations I have to assume (because I have never done it!) that the ability to explain one's decisions, emphasising the paramount importance of safety must also be a pre-requisite for the job.
Nobody wants to come a cropper. Not even the super rich. Some actually like having key individuals around them who are prepared to prevent them forcing a dangerous situation. But it is their right to have each occasion explained to them in however much detail they require. Because some pilots can equally be over-cautious/obstructive/under confident.