I was referring to proving the non-existence of a fact. The article admits that this is not possible.
Whether or not NNVC is a scam is, if true an empirical fact. There is no way for me to prove it is not a scam. I can point to the absence of evidence but we all know the absence of evidence is not evidence of absence.
The article was "cute" but not persuasive on the point, and the tone is somewhat tongue-in-check.