Clint Faraday book two: Daybreak Collector's edition

A man calls from Puerto Armuelles. He has somehow stepped on the toes of a mafia don. Clint investigates. It is some kind of scam about a fake oil well - but a mafia don or two are definitely involved. What does counterfeit money have to do with it? Who are the obnoxious tourists? Why are they there? Why is a woman murdered?