I was thinking about Tuyet the other day, trying to piece together her story in mind, when I realized a strange inconsistency in the story, specifically regarding her decoy in the Pit. Before I begin, let's take a look at Tuyet's involvement in the story so far.
Tuyet was a member of the Toa Mangai and started killing Matoran on Metru Nui to frame the Dark Hunters (who were coming after her to get the Nui Stone). Lhikan destroyed the Nui Stone and embedded it in her armor. The Order of Mata Nui placed her in a pocket dimension with no Toa and put a Tuyet from an alternate dimension in the Pit as a decoy. The decoy died in the Great Cataclysm, and Teridax attempted to use the Staff of Artakha to restore the Nui Stone using fragments from the decoy's corpse.
Here is where we encounter the problem: why was there a corpse?
Theoretically, the decoy Tuyet should have transported to the Red Star after her death. If we're looking at real world explanations, I'd say that Greg simply hadn't thought of the Red Star revival mechanism yet. I can think of only two in-universe hypotheses: 1) Because the decoy was from an alternate dimension, the Red Star didn't recognize her, or 2) The decoy died outside the Matoran Universe, and (as suggested by some on BZP) the Red Star only works on those inside the MU.
Neither hypothesis accounts for why Teridax went looking for her corpse in the first place. As an inhabitant of the MU, corpses should be an unusual sight for him, given that as long as there is a body, the corpse should be teleported to the Red Star. That also raises the question of why he needed Matoro for his Mask of Reanimation or why such a mask would be necessary in the MU at all.