The game requirements say nothing about OpenGL, only DirectX. As far as I understand it, they're competitive and can't be used together.
Is it possible that for some reason you're using your onboard graphics instead of the Radeon? Like connecting your video cable in an upright position in the rectangular backplate instead of horizontally right into the video card (seen that several times)? Or not assigning the 6700XT for playing AH in the AMD video software?