Steps to reproduce:
1. Ingest a recording that is attached to a series, make sure to activate "archival"
2. After publishing, use the search REST docs at /episode.xml?sid=<series id> to make sure the recording is part of that series
3. Next, visit the archive and use the metadata editor to change the recording's title
4. Apply the "Republish" workflow to push the update to the search index
5. Now check the search REST docs again
The series does not include the recording anymore, however searching for the recording by id or even fulltext works.
The recording is stil part of the series.