I don't know about a swiss cheese event - when two people with no CRM skills and a limited knowledge of the AP functions are let loose it's a matter of when, not if, there is going to be an accident.
They were undone by a combination of poor CRM, poor handling and management skills and poor awareness of the risky profile (until the last 10 seconds!)
I mean "Swiss cheese" in the sense that it is possible that the single occurrence of activating the collective FTR could have been the difference between meeting the water at 150kts and maintaining enough collective to remain clear of it until the aircraft was stabilised and clear of danger given their attitude after activation of the AP upper modes. A single factor such as that
could have been the difference between this thread and nothing worth reporting on at all.
I agree with you on all other factors though (and I find it very intriguing that the SIC was apparently aware of the G-LBAL incident but didn't realise the parallels until 10 seconds before impact - I do wonder what it would've taken for him to realise the similarities sooner and possibly avert the tragedy altogether). At the end of the day I do believe they were capable of getting off the ground cleanly, but that would have required max 5 minutes' worth of briefing and planning on the ground at the island which clearly was not done. As was mentioned above - agreeing on a defined departure profile, and under which circumstances the PM would assume control to prevent a loss of control would have been sufficient. We can all agree that the CVR shows no evidence of this (as far as I can interpret).