I think it's important to remember in the case of the Black Rose scientist we're dealing with the Eorzean Alliance and with Yotsuyu, Doma. Their motivations for their crimes differed too--not that it excuses either of them. I just think it's a bit fruitless to compare, different people who committed different crimes and sentenced/given judgement by different bodies of authority in different parts of Hydaelyn. The amnesia is the only common factor for these Imperials, and while a pretty compelling basis for comparison I feel things would've played out different had, like, Tahla Molkoh petitioned Brookstone that Grillairmais' crimes could be excused/his survival in part of the Elemental's will etc. etc.