Hello WW,
Very nice and interesting knife!
Just a guess, not many people here heard about a Chamorro knife before.
Here about the Chamorro:
https://en.wikipedia.org/wiki/Chamorro_people
And here an old thread:
http://www.vikingsword.com/vb/showthread.php?t=15161
And two other fairly old Chamorro knives I found online.
Regards,
Detlef