Thank you for that! I tracked 'Solitude Exterior Sovngarde Statue Set' down to Modular PatchXPress (MPXP). rockl04_lod_1.nif was in it's mod folder under the meshes as I would expect it to be. I would much rather it had been missing, because now I'm completely lost as to what's going on. Why does Dyndolod not recognize this file's existence? Is this most likely user error on my part somewhere, a problem with the mod, or a Dyndolod error?
It's weird that I had previously searched my mod folder for "rockl04_lod_1.nif" and it didn't find it. Gotta love windows.