I'm uncertain if my Direct Message was received, however, regarding this pre-Maori tradition, are you aware of the much debated yet under-publicized New Zealand North Island anomaly known as the Kaimanawa Wall..!?
It's smooth faced surface area and horizontal joinery appears somewhat similar to what we find scattered across the Bolivian Altiplano. Sea-faring by nature, it has been suggested the Maori (and their ancestors) may have made the dangerous, yet otherwise logical journey, across the Pacific to Easter Island - home of the Moai, whereby they'd continue east to South America...
What, may I ask, are your thoughts regarding this pre-Maori structure and migratory thesis?
Kind and Spirited regards...Richard