PIC?
Yes CASA, Pelair, REX group and the ATSB have many serious issues to answer for as highlighted by the legislation, the level of oversight, organizational structure and effectiveness, depth and clarity of investigation etc. etc.
The fact still remains that when all of these are over the horizon and you are seated at the pointy end of a jet, the decision to proceed with the return journey when you know (or should know) even by company standards you are fatigued, the decision to take less than full fuel and the decision to fly past possible alternates are all COMMAND Decisions.
The patient could have stayed in hospital at Apia with the extra care from the Careflight doctor and nurse for another 12 hours until the crew were rested. The lady did survive a ditching and was not in a critical condition.
Bitch and moan about royal commissions, more investigations, better navaids, better weather reporting, changes in legislation and putting the cleaners through every organisation that have had anything to do with this near multiple fatality but the fact remains had different decisions been made the return trip would have been nothing more than a log book entry.