Comment 4 for bug 1128492

Thank you for the bug report Rick.

There is a long standing known issue: user wallpapers, if stored in a non world readable directory, are not visible to the greeter. That's bug #928553. The reason is that only the URL is shared (to not "leak" private infos), so the greater (which runs as another user) needs to be able to read the file to display it

Is the directory the image is stored in world readable?

Not sure that's the case there though, since you seem to do twice the same steps and that should lead to the same directory to be used/result

if you run "gsettings get org.gnome.desktop.background picture-uri", does it list the correct image?