Understandably, there is a fair amount of discussion about these cancelled flights on the Cook Islands section of TripAdviser. It seems that NZ is giving different explanations according to who is talking and where. One reason given is problems with landing lights at Rarotonga airport or staffing issues in LAX.
https://www.tripadvisor.co.nz/ShowTo...k_Islands.html
Obviously NZ are having problems but it would seem sensible for them to issue a press release on the matter, not only for those passengers affected, but also others who may be affected by the trickle-down effect. I think also the general public should be advised of what actually happened.