Thanks for resurrecting this thread. I actually wanted to ask the same question.
More research needs to be done in this area before it is too late. The following of Visayan weapons seems to be snowballing now. I'd hate to see a lot of 'false' history being spread due to the fast growing popularity. Obviously with no clear cut history and research, a lot of Filipinos will be quick to tell their own made up stories/versions on how certain weapons came about(I see this a lot now in FMA).
I hope to hear more from Lorenz and Nacho as well.