Do you mean everyone as in everyone in the series or everyone in the fandom or both? If you mean the fandom, then there have been plenty of theories and speculations that Lacie might reappear at the end, many have been expecting it. If you mean in-series, than I agree. Though, I don’t necessarily agree that Jury and the others lied about anything. It seems like all the previous CoM truly were destroyed when they got dropped down into the Abyss during the Glen Succession Ceremony, but Lacie was special because she 1. was shown to have a deep connection with the Core of the Abyss and 2. (likely more relevant to why pieces of her soul may have survived) she was pregnant. I
never really thought about this before, but this ask made me realize that Lacie literally gave birth as she was dying. This whole idea and concept kind of represents the action of being reincarnated/reborn, something that Lacie was going to be denied due to her CoM status and her role in Glen’s Sucession Ceremony. Lacie was special, which is why pieces of her soul may still be lingering around.