Key point: I don't have to speak Tongan or be able to write in Tongan to notice certain surface features. A monolingual teacher can notice the strengths of bilingual students with the right lenses on!
Update on my research... I am going to try and use one of my release days this term to meet with Rae Si'ilata who was an amazing past lecturer in my TESSOL paper and who also featured in this Month's Listener Magazine in an article about the importance of vocabulary and language acquisition.
I have also tried including different languages in other areas such as Maths, in which I am using Maori numbers as a basis of my place value lessons. I am also aiming to use Tongan number counting with my target group.