In all the time I've spent in Hawaii, I've never seen this tree BUT, on the chance that the brightly shining sun affected my vision, I'm wondering if you'd check out this tree and see if it might be familiar to you.
Assuming it is something close to a tricolor Hibiscus tilaceous - I don't know it well enough to tell, myself - it could be one that has only had local distribution or otherwise is not accounted for in the literature, for other reasons - like never being given its own name or being registered with a cultivar registration authority. Or, just maybe this individual tree is the only one, a sport of 'Tricolor' or another more familiar one that has not been recognized and dispersed from this location much, if at all.
In the meantime, keep looking at descriptions of H. tiliaceous cultivars (or those of other likely plants) on web sites and in books that focus on hibiscus and related plants, to see if it turns up. Keep in mind that it may not actually be a hibiscus, but rather a related genus, too, if that remains a possibility.
I'm sure I saw the same variety in Noumea, New Caledonia 3 years ago. I photographed it too but that was in my pre-digital days. I have never seen it elsewhere and I am quite familiar with the normal wild form of H. tiliaceus (note spelling - important for searching!) and there is also a purple foliage form grown in Australia.
So it looks like your plant may be a cultivar as yet known only in French Polynesia and if it has a name at all, you would have to go back there to find it.
