hi,
i live here on rarotonga in the cook islands. yes the GTs here have a very high chance of ciguatera. some locals still eat them and take their chances though so not every fish has it but not a risk worth taking in my opinion as it is has nasty nasty neurological effects. one guy here got medically evacuated to nz about 2 years ago, was in hospital there for about 4 months and now looks like he has had a severe stroke, he is almost handicapped now with slurred speech, loss of normal functions and is in a bad way, all from ciguatera as he was an active, healthy man before hand.
the game fish here such as wahoo and yellowfin are fine.
some good gts here in rarotonga, not really a secret... but in the outer islands of the cooks group there are some absolute beasts around that have no one targetting them with poppers at all................. google search, manihiki, rakahanga, penryhn, mangaia, pukapuka.
lots of locals on the island of aitu for example have never seen a popper or a braid set, they laughed at me with my little casting gear (popper rod, 80lb braid and spin reel) but were soon converted.
www.fishing.net.nz/asp_forums/atiu-cook-islands_topic67690.html lots of undiscovered adventures to be had if you have the time and put in the effort.
aitutaki has some great gt action also.