I came across a page on the web that listed over 50 explanations for the DNC acronym. But this one is not one of them, and it is a battle cry for those who do not believe the official story about COVID. Based on the official account, there are too many discrepancies, which makes this conware...
But on most occasions, human beings have the right to refuse a medical treatment when they do not agree with it, and of course the exceptions to this are minimal, so unless they declare an anti-vax attitude a mental disfunction, "Do Not Comply" is still common sense.