If we get that IMO it's worth it to try to crit it as a 5% discount is neat, but not gamebreaking, but 15% and more options for further discounts would be a bigger deal. So maybe go for it in a turn Anexa has nothing better to do and stack the odds?
Do we actually need the captured cultists for anything? IMO just give them to Denva, they are going to need to deal with and give therapie to far more cultists, having to deal with 500 more shouldnt be a big deal. Especially if we also give them mood regulators since those combined with the cognition filters and detection tech should give them all the tools to find and humanely deal with anyone exposed to Chaos.
I don't disagree that better results for Superconductive Shenanigans would be better but "a turn Anexa has nothing better to do" is going to be a long time coming.
I expect the cultists to come in handy at some point for a variety of technologies, although I wouldn't object to giving them to Denva. Having people we know are corrupted should be very good though for the potential follow-up tech to The Taste of Chaos that might be able to detect individual cultists/corruptees, as well as Chaos Corruption Cognitive Intervention to outright de-corrupt them. Probably some other applications as well.
I'm doubtful of the degree to which mood regulators would help the prisoners themselves, we already have a tech for an implant that helps outright corrupted people and it's the significantly more expensive Chaos Corruption Cognitive Intervention. Mood redulators are "Useful for those engaged with Chaos" so I'd expect them to help keep the attrition rate down for Denva's thought police, not "humanely deal with" outright chaos cultists.