Scorpius being the result of race mixing was only hinted later, no? At least that's how I remember it. And I do believe that Zhan's crime was mentioned in this thread before teacake saw the episode which revealed it.
I did watch the show without subtitles, so I might've missed something. I any case, watch out for spoilers...
Scorpius being a hybrid plays a pretty major role in stories later in the series.
Really, what's so hard to understand about a spoiler free