North America had the latest release of DKS (aside from the eventual retail re-release in the UK), which was caused by problems getting a publisher. I'm not familiar enough with the details of the Benelux release to use it as an example. The German publisher was on board very early, so presumably that had something to do with that release being first.
Retail may not be important for you, but it would be for any publisher in a region. Distributors would be concerned about previous digital releases, as well. A distributor for the retail version of the anthology requested the exclusive D:DC and D:OS DLC items as something extra to help physical sales, though I'm not sure if that was to compete against the digital versions of the anthology or just to help it stand out in the retail space.
