I've got the exact same challenge, after half a day of doing this I believe I've gone through all the steps and thought this would be it. However, I am still getting no blob or key found (despite renaming ext to .file and being saved under chrome) and now the auth is failing despite all the details being correct. Any ideas or suggestions will be very much appreciated. The auth worked prior on none DRM protected downloads when I hadn't attempted the blob / key steps.
OF DL message below - why now woud auth be failing?
auth.json located successfully!
config.json located successfully!
yt-dlp.exe located successfully!
ffmpeg.exe located successfully!
mp4decrypt.exe located successfully!
WARNING No device_client_id_blob found, you will not be able to download DRM protected videos without this
WARNING No device_private_key found, you will not be able to download DRM protected videos without this
A tutorial to get these 2 files can be found here:
Auth failed, please check the values in auth.json are correct, press any key to exit