I’m having the same problem as well. Files are viewable in CLI, but Sonarr can’t see any of it. Everything is the same user, I’ve even set most to 777 to try to get it to work.
I did manage to get it to work by fusing rclone mount and another folder, and pointing Sonarr to that. Then I tried using the same method on a VPS, and it won’t see the rclone mount or the fuse.
If I figure out what I am doing wrong I’ll update.