2023-12-04, 02:42 AM
Update/solution: I attempted to create a second Nextcloud instance to start from scratch and try to upload files through there to see if a completely vanilla instance would resolve the issue, but ran into issues and wasn't able. However, something reminded me about having the files encrypted, so I tried turning that off. After disabling encryption on the files, Jellyfin can play everything fine. If I recall correctly, encryption is not a retroactive action with the default encryption module on Nextcloud, so that would explain why the files I uploaded when I first migrated would work but not anything else.