I think the confusion comes from on the one hand getting command help, on the other hand getting gstreamer help.
This is fixed upstream, see ticket https://thomas.apestaart.org/morituri/trac/ticket/12 and I'll make a release sometime soon. -- To UNSUBSCRIBE, email to debian-bugs-dist-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org