I don't think Madeline going to Challenge Cup necessarily means she'll be chosen over Alison if Emily fails to get the minimums. SC may just want to have a backup option in case Emily doesn't get the minimums and then Alison gets injured last minute, or something similar.
Karen could be named to the team and then later decline. IIRC in prior years funding/meeting envelope criteria has been tied to being named to certain teams (or being an alternate to such teams)
Nonetheless I really hope she goes :)
According to this https://www.teamusa.org/Lausanne-2020-Winter-Youth-Olympic-Games/Meet-Team-USA/Roster Hanna Harrell and Audrey Shin are going to the Youth Olympics
I'm assuming Alysa Liu declined since she would have been the most obvious choice
I'm quite :huh: about Shin as she was...
She's off the list for Russia as of today: https://isu.org/docman-documents-links/isu-files/event-documents/figure-skating-4/2019-20/grand-prix/series-files-27/entries-4/21487-entries-ladies-2019-20-all-6-events/file