This story is evolving rapidly as some evidence is showing up that it's the CAQ (the party currently in power) that first tried to push the existence of the DARC blog post to the journalists, then informed CSIS when they didn't report it since it seems to be just one blog post from a think tank, not a coordinated effort.
https://ici.radio-canada.ca/nouvelle/2287702/caq-scrs-ingere...