Sikozu was not originally meant to be the spy. It was going to be Noranti, but the actress was having issues with the makeup, so they reduced her role in PKW. If you look, there are actually two different actresses playing Noranti throughout the movie.
I don't know that it's confirmed
that Noranti was originally the spy, rather than simply suspected
, based on what is
confirmed - that Noranti was originally going to have a bigger role until she had problems with the makeup. (She really was Zhaan 2.0.) Unless there's something I missed.
I thought I read it in an interview somewhere, but I can't remember. Although it does make a lot of sense, especially since in "Bad Timing," Scorpius orders the "elder cook" to be brought aboard the next time they encounter Moya. I don't know why else he would be doing that if she wasn't supposed to be a spy.
Or here's a wacky idea that occurs to me just now. People go on about how the Scarrens kinda look like dinosaurs. What if they are dinosaurs? What if the Eidolons went and picked up some fearsome creatures to be their warriors even longer ago, but lost control of them and somehow created the Scarrens, who evolved over the millennia into the forms we see now? And in an attempt to correct their mistake, the Eidolons went back to the same primitive planet and picked up the latest dominant lifeform there for their next go round? Actually never thought of that before.
Wacky idea, indeed. But this is Farscape, so it probably would have worked. The Eidolons probably stole the Bird of Paradise flowers at the same time and somehow used them while genetically altering the dinosaurs.