I was focussing on the worlds with UWPs, not just all mentions. As of this post I've pulled 17 systems fitting that criteria from JTAS 4 - Challenge 32 and found one world without a UWP mentioned in relation to one of those.

When I looked at your list it looks like some of the ones I found were on your listing, but I actually found a few that were not, if you want I'll send you a copy of the list I have compiled.

...I have not spoken of the work Santha and I did in the South Pacific around the Tahitian islands of Taiatea and Huahine, or of the strange things we saw underwater off the Tongan island of Haapai. (Graham Hancock, Underworld 2002)