I foolishly restarted DynDOLOD, changed a setting, ran it to see whether it would magically made grass lod work again and shut down the program the moment I saw the grassless meshes coming in, which completely wiped out the previous logs. It's past 1 am where I am so it's too late to run it again, so the logs would have to wait. One thing that I noticed though: in the LODGen logs that I uploaded, the "grass mapping not found" messages got the form ID of the grasses wrong. As in, the generated billboard of a grass is named "xxxxxxx_000008xx.dds" but LODGen was seemingly seeking a file named "xxxxxxx_000000xx.dds". Hopefully this counts as relevant information.