The filename in the git repo was changed from "pytorch_model.safetensors" to "model.safetensors": https://huggingface.co/mcmonkey/google_t5-v1_1-xxl_encoderonly/commit/b13e9156c8ea5d48d245929610e7e4ea366c9620
The save path has a typo - it saves to the "diffusion_model" subfolder (no "s"), instead of "diffusion_models"