Another workaround that will allow me to not confuse Plex:
I have temporarily made aliases (Mac) or symlinks (*nix) for the so-called unlisted files in the imports folder.
This allows me to let Channels DVR to do its normal recordings and Plex to scan the normal location.
If any FURTHER files show as unlisted I can simply alias/symlink them until this bug is fixed.
I am at your service to help in any way to permanently resolve this issue.