I've addressed the issue as well. I find it extremely hard to believe Vergere was a "Sith candidate" who apparently had enough knowledge of Palpatine's nature that she recoiled and he sent assassins after her. And conveniently instead of telling the Jedi council or even assuming that she wasn't going to do that going to Zonama? That was extraordinarily convenient. Then meeting Lumiya? How? When did Lumiya learn of Vergere's existence? How did Vergere contact Lumiya when with the Vong who observed her constantly? It's stated they had some conversation discussing which member of the sky solo clan to turn(and Kyp Durron)-I ask again, how? How would they have these in depth psychological profiles of what at least 6-7 people they had only barely met if at all. Everything about Vergere's alleged Sith background from her interactions with Palpatine to interacting with Lumiya during the Vong War doesn't make any sense or it only does with massive stretches of disbelief and an extremely generous accounting for timelines.