She wasn’t really behind the Reactor meltdown.
She was there to work with the Inquest but from what I see from her dialogue, it sounds like the Inquest wasn’t really listening to her of the dangers there.
And the reason why the reactor had a meltdown was another thing. The Inquest experimented on one of the worst possible locations to experiment on magic. It was on an intersection of the ley lines. Something they discovered too late.
So she (Scarlet) was there to work with the Inquest, strange, because, Dezza told us that as she know, the Reactor hasnt blown up yet and there were people in the inquest working there, that she knew. Dezza also said that she doesnt know what a Sylvari is. Doesnt that mean that at the time, they worked on the Reactor, Sylvari hasnt been born because Dezza dont know Sylvari yet? sry for my bad english