Chances are that indeed there is only one tree left originating from Curacao and that your dad is part of it. My father's name is Jose Maria Cijntje, they might know eachother. He did mention family abroad in Sto Domingo, Miami and somewhere else in the states once. The dutch ancestry seems to have died out somewhere in the 1800's. A cousin of mine did find a record in 16-something in a town called Beertha in the north of Holland. We haven't been able to figure out if he's family yet.
My mail is arti_cijntje if you want to mail direct