VX? Possible, but, I would not expect the women to live.

VX liquid has been proven to be very unstable. It will dissipate into inert elements within 12 hours of exposure to any carbon surface, including concrete. I am surprised it lasted on his face long enough to be detected. What about the emergency workers that attended to him and the train personnel?

February 23, 2017
By Thomas Maresca

Singapore —  VX nerve agent, (click here) a highly toxic chemical, was used to kill Kim Jong Nam, the estranged half-brother of North Korean leader Kim Jong Un, Malaysian police said Friday.

Police Inspector-General Khalid Abu Bakar said the substance was identified in a preliminary report by the department’s Center for Chemical Weapons Analysis.

Kim Jong Nam died Feb. 13 shortly after two women put the substance on his face while he was checking in for a flight at the Kuala Lumpur airport in Malaysia's capital.

The report identified the substance as ethyl N-2-Diisopropylaminoethyl Methylphosphonothiolate, or VX nerve agent. It is a chemical agent classified as a weapon of mass destruction by the United Nations.

Traces of the nerve agent were found from swabs of the face and eyes, the release said....