I got this to work via separate Python code that:

1. Creates a library of skies with gendaylit for all the hours in the weather files I'm looking at.
2. Makes an octree using oconv with the appropriate sky and the model.rad and materials.rad generated by OS/Radiance only if the sun is within view of the window (by azimuth)
3. Makes a fisheye HDR image with rpictand that octree and the parameters from the glare sensor files generated by OS/Radiance
4. Outputs the glare metrics using evalglare