"Onde estamos" não está se concentrando na localização geográfica do falante, mas sim o estado do mundo (= o seu povo). Moana mudou seu mundo, e ela está reconhecendo esse fato quando diz "Eu entreguei-nos onde estamos".
É o equivalente a dizer "Eu fiz o mundo do jeito que é hoje".
Para ampliar ainda mais isso, encontrei a seguinte nota no Genius :
Here the wayfinder from “We Know the Way” is seen sailing past Moana and is seen to recognise her as a way finder herself. She has found her people’s ancient identity and her own and now they have affirmed it.
This is a big moment in the film as it’s the passing of the torch from 1000 years ago. The chiefs used to be people who kept their fleets safe and widened their people knowledge however Moana’s father has kept their people safe poorly by restricting their knowledge. Moana has learnt the ways of the past now and can take her people back to them.