No download option for ATN

I purchased the ATN dlc from within Halo Wars 2 on PC. I now cannot find an actual download/install link for it. When I go into My Libray on the Windows Store it says that ATN, as well as all the other ultimate edition DLC, “doesn’t work on this device”. I know it’s not a device issue since I have the original game installed. At one point I located a link to “install on xbox one”, but have never found a way to get it on PC. It seems that only the xbox version is showing up under the more games option in My Library in the windows store.