Well, I finished reading the investigation report. I see absolutely nothing in there to support the notion that the boys were kidnapped. It was a tragic boating accident.
I do understand know why there was so much confusion about where the boys were going and whether or not they were allowed to go offshore on their own.
Perry's dad (or step-dad, I forget which) says that Perry wasn't allowed to go offshore without an adult on board, and that rule was re-confirmed with Austin when Austin's boat was purchased. But Austin's mother says he was allowed to go offshore, just not "way offshore," and Austin's grandfather says that Austin's mother set the limits for where Austin was allowed to go in the boat, but that he (Austin's grandfather) "didn't think there was any."
They told Austin's grandmother that morning that they were going fishing for dolphin -- which you do offshore, not inshore. And they had apparently been fishing offshore the day before, as well. So there may or may not have been any sort of rule about going offshore, and if there was, it appears that it was largely ignored by everybody.
They told some people they were going fishing offshore, and they texted/SnapChatted some friends that they were "Bahamas bound." They told at least one friend they were going "far out" offshore. Probably just boys talking tough, but it does explain the confusion about whether they might have been heading to the Bahamas.
But I saw absolutely nothing anywhere in the entire report to suggest they met with any foul play. They were victims of foul weather, but not foul play.