I know it is not antique but if you read all the information, Santa Ana Island and Santa Catalina Island where still practising traditional beliefs even in the 1960s so as far as I am concerned we do not know how it was collected. We know the social context of the form. Could quite possibly have been the kind of thing missionaries bring back.
Interesting made for the market stuff here. Some what different?
https://www.youtube.com/watch?v=MzNJ_km93S8