Justice and Faith might be problematic, depending on how Cyrus views Psykers and the reactions of his superiors here. If he can be convinced that he is a danger, and that he's 'wrong', then I can see him going along any restrictions they may place on him.
Though his boost to Power, and his low Duty, maybe mitigates that?
I think it does. His Duty is his lowest Drive; he just flatly does not
do things because some higher power tells him he is supposed to. He is imbued into the culture of the Imperium as one of its citizens but Covyria frankly seems like a bit of a backwater, and its pretty obvious that they both know he's a psyker and want to talk to him about it what with Hakor being pretty clear about secondary concerns and the implications there. Both of these people also care for Cyrus, and are essentially his dad and his funny doctor uncle.
Justice has to do with what's right, an idea of fairness or balance in the universe, and Faith in the context of Cyrus is the sort of in a sense emotionally simple quest for knowledge of the Mechanicus. The skills aren't really tied to the Drives, that's simply not how the system works, and as we know his Power Drive is based on the idea that he wants to survive to do and see more. To grow as a person. His Truth just ended up where it was because Truth is a means for him to decompress without stress and just tinker with things.
So I think in some sense he believes that rightness can be found in the Quest for Knowledge, but also that it is right to protect his friends, to help people, and to give some kind of information to his robo-dad not because its what he's
supposed to but because Hakor is someone he cares about and who deserves to know. There's also the consideration of,
why these two put in the cranial implants: they've been in Cyrus for a long time IIRC so this has probably been a thing Hakor and Rho-Eta knew about for a while and the both of them do genuinely seem happy he's not a drooling vegetable or otherwise seriously harmed which is a point in their favor given they seem to know he's a psyker when he doesn't.
Plus, this is the mechanicus, and there's actually very little lore that I can recall on them being explicitly harmful to Psykers (other than being the folks who maintain the apparati of the Golden Throne and other technical devices of the imperium which make use of psykers), to psykers in and of themselves in the same way the Ecclesiarchal dogma proclaims.
-[] All. He would reveal everything that had happened to him, and his new state of existence.
--[] Write in: Start at the beginning, be factual, be truthful. When it comes to the battle with the Tyrant, he's pretty sure that was a psychic duel of some kind and that he beat it with memories of human experience, need, and the doctrine of the God-Machine. How its mind is gone, and the flesh now under his control like some servitor or similar device. He's probably some kind of psyker, and he's not ignorant to the fact they probably knew that, but an opportunity to do the right thing, to protect Covyria, his friends, and to advance the Quest for Knowledge has effectively landed in his lap and he needs help to make use of it. Present this as an opportunity, if a terrifying and disturbing one.
Basically, I think we can trust these two. They could have killed Cyrus when they realized he was a mutant or abused him, and crucially they don't seem to have, and more than indifference seem to actually care about his well being. If nothing else I think Rho-Eta will be on his side and Hakor seems to respect Rho-Eta.
E: To be clear, I'm basically aiming for using Justice or Faith here if we need to roll something.
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