One of the first medical responders called to a luxury hotel in Mexico where two Americans were found dead earlier this week ruled out carbon monoxide poisoning as a possible cause of their demise. The possibility of a gas leak was immediately nixed when they were called to the Rancho Pescadero in Cabo San Lucas where Abby Lutz, 28, and John Heathco, 41, were found dead Tuesday, paramedic Erick Abundis told Spanish-language broadcaster Telemundo.