Seems Lucien isn't Sion. Yet. He's rejected the idea of becoming the Lord of Pain. He is however lost his eyes and his hands our burnt. See Lucien Draay's entry on Wookiepedia for more info.
I don't think the KOTOR comics are sold in the UK so could someone post me a scanned image of Lucien at the end of the comic. Wookiepedia don't have one.