You have to make sure the display for all devices is exported on linux for all cards to be seen with "export DISPLAY=:0". NFI what you need to do on windows.
It was suggested on IRC that since we are exporting all the displays like an active one in linux, it may be that the lack of outputs on the displays on windows is why the adl library isn't talking to them. i.e. perhaps it's only the cards connected to monitors or dummy plugs that work.