Even disregarding the polygraph, just by having the locals suggest she is alive would create doubt that she is dead. They may have deliberately floated the idea, so the guys could go free.
Regarding the comments about Urine von Dipshit being hooked up to wires and cream being used, it sounds to me like they may have been checking out his heart. May be that the boy was hyperventilating or had chest pains or a severe anxiety attack. Could have been a medical procedure. This could have been the source to the suicide rumor.
If and when this is resolved, I suspect the people of Aruba will rue the day they underestimated the tenacity of Beth Holloway Twitty. When it comes to protecting children, mothers can be relentless.