Sure.
In China, there's a TV show something like American Idol (and other ___ Idol shows from other countries) called Super Girl.
Junjun auditioned and ended up as one of the finalists. Of course she didn't win though.
So, Tsunku (or whoever made the decision) wants to add in a couple Chinese girls to add some international appeal to Morning Musume.
He's already got Linlin in the Eggs, who has been on Chinese TV since she was little and was supposedly recommended to Tsunku by someone.
But where does that leave Junjun?
Without telling anyone, Tsunku holds a private audition (I forgot if thus was in Beijing or Tokyo) where only the Super Girl finalists are invited.
Next thing you know, we get the first two non-Japanese members of Morning Musume.