From what I understand the Japanese area would include animals. Given that there are already islands around, I would assume their existing Japanese macaque group will be included.
The South American primates I see listed on the website under Cambron Abbey are those that live in the Oasis semi-arid greenhouse (sakis and cotton-top tamarins).
I personally really like the look and feel current tapir/capybara/tapir exhibit, I hope it will be kept more or less in its current form even if they move the South American animals. But the inhabitants would have to be somewhat aquatic and not too large, so not that many options.
Personally I do not really like the idea of them building a massive tropical swimming and wellness facility. Too much of a theme park feeling and too distracting from the mission of modern zoos, I think. I understand them including accommodations, but I would prefer if the majority of the area would have a focus on animals, ecosystems and conservation. But it wouldn't be Pairi Daiza if they did not do something weird with it...
An article I read mentioned "Colombian ruins" as part of Sanctuary. I assume that would mean some kind of Inca theming.
Personally I don't think The Land of Origins is that weak, and has a reasonable number of adequate exhibits, but also some poor ones. The area I personally like the least is The Kingdom of Ganesha, as the aspect of excessive theming at the expense of animal exhibits and welfare is in my opinion the most notable in that area.