
I do agree with you that the piece shouldn't be classified as Dahb. But it 's not unique to the island part. Parang style weapons are also exist in mainland Malaya peninsular too. This one is a good example
The forge-weld blade 's made in wakisashi profile (3rd blade from top of this rack). It 's made with keris/badik technique. There is a document that in the 19th cent., similar blades were made and the Siamese king sent "keris-patterned Japanese sword" out as a diplomatic item.