Actually there is a lot to read about the possible reasons for the death of Kim Jong Nam. Beside all those theories I also like reading tea leaves: First: A group inside the elite (possibly from the military or security circles and not from the Kim dynasty) works as a stand-alone organisation, willing to build up another type of regime. Their aim is to eliminate the Kim bloodline and all who are loyal to the Kims. Second: Since approximately three years there are concrete plans to conduct a covert, maybe a clandestine operation, targeting the elite in North Korea. Those people took a look into the Kim family and draw a huge graph, conducting Social Network Analysis. They studied M. S. Granovetter, “The Strength of Weak Ties” (1973) , and came to the conclusion, that „removal of weak ties, starting from the weakest link and working up, caused the communication network to break apart, while the removal of strong ties had little effect on the overall integrity of the network.“...
"Information at best will always be in some part fragmentary, obsolete, and ambiguous." (Armstrong, Willis C. (et al.): The Hazards of Single-Outcome Forecasting, in: Westerfield Bradford, H. (Ed.), Inside CIA's private world, Yale 1995, p. 242)