What a terrible tragedy for a helicopter company with an exemplary record. I am speaking as a chopper pilot who has previously flown to the Panda Ranch on Molokai and would describe the trip as a straight forward one.
I note references to a downpour but I doubt it was inadvertent entry into IMC because Blue Hawaiian's EC130s are equipped with terrain mapping screens which I believe are guided by GPS.
Thoughts and prayers for the victims and their families.