MOO MOO MOO MOO
I imagine if they had been successful in getting off the island, they would have taped the suitcase up and said they were staying another 2 nights. At night, go throw the suitcase in the ocean. Go to consulate and attempt to get passport. Get off island and back to US before anyone figured out Sheila was missing.
But I wonder if they would have been able to pull this off-- get themselves to the US. Seems like there were so many problems and they were rather messy (a good plan would have at least required them to clean up a la Scott Peterson). Seems they should have stayed status quo at the St. Regis. But, we don't know how much of a struggle or what other people heard. I've heard the people in the next room having sex once and they weren't particularly loud... The walls were that thin. Seems there must have been a rage on HM's part which, to me, implies screaming. We already know they were shouting at each other in the lobby. I'm certain there would have been shouting in the room enough to get HM all enraged, "not able to take much more of it" and then "wham!" Bash Sheila's face in with the first thing she could get her hands on to shut that "b---h" up. I imagine the first blow went to her mouth. I wonder if Sheila had any broken teeth? Or maybe she was aiming for the mouth to shut her up but hit the nose area instead. Maybe Sheila saw it coming and in a split second lowered her face downward to try and protect it and HM's blow got the top of the nose, by the brain? MOO MOO MOO MOO MOO
ETA: links on nasal trauma:
http://www.healthline.com/health/nasal-trauma. "In some cases, a nasal fracture can damage the bones that attach your nose to your skull. This injury can allow cerebrospinal fluid to leak."
Maybe Sheila choked on blood and spinal fluid?