Hey Guys, I Wouldn't Worry About Viktor's Lore Just Yet
I mean, although we have what's basically a transhumanist cult that wants the same thing as Viktor (augmented humans with hextech limbs/organs) I doubt that Viktor and the cult are related. For an example, take Dishonored 2, for those who've played/seen the game. We got the main character using all these magic powers, but they don't really show any devotion or belief in the entity, the outsider, that gives them their power. Meanwhile, there are shrines to the outsider scattered across the game as well as witches who are obsessed with the outsider and the power he gives. Viktor is sorta like that, he has no devotion or religion that has to do with transhumanism, it's just augmentation, not the will of some god. The cult, on the other hand, has a full religious devotion to this "Grey Lady" and even give her offerings. Do we see Viktor putting his old arms and legs in jars and placing them at an altar? No, so I don't think we have to worry about Viktor being some religious zealot.
TL;DR: Viktor and the cult share the same views, but Viktor does not have the same religious devotion to the "Grey Lady" as they do.