I know how the Presidents Cup dynamics are constantly in your hearts and minds so it is with my deepest apologies for passing along incorrect information. It regards Brooks Koepka's non-member days not counting toward his Presidents Cup standing. I regret not having fact checked the blog post I linked to.
In fact, Koepka is credited with Presidents Cup points dating back to start of the qualifying period, the 2013 BMW Championship.
However, I do stand by the rest of my views that the PGA Tour needs to reconsider how it treats "non-members" who make the playoffs but don't make the playoffs, and consider the long term ramifications on college golf if there is a view that players can't finish the school year without harming chances of making the playoffs of either tour. (WGC winner Shane Lowry could have been part of the venting too, but I'm more concerned by the route from elite college player to tour.)