The argument that grabbed Kireh, when she was a Lawful Good angel, was basically just an offer of power, aimed at her frustration at helplessly watching people make mistakes. When she recruited other angels, some wanted control like her, some were tired of tearing themselves away from interesting tasks as soon as they were no longer the highest priority, and some wanted to be emotionally resilient outside the hothouse of the Good planes. Or they were recklessly fervent, ready to destroy themselves and become whatever Marra needed, in order to oppose Asmodeus.
When mortal Marrans deal with Lawful Good, they usually focus on Law and avoid each other. Recruiting from Lawful Good is rare - there are enough desperate already-Evil people to choose from.
If only this follower of a Lawful-ish Good god had a better understanding of Law... but this universe doesn't have systemic alignment.
She could say 'followers of Marra are allowed to be nice, if it's clearly marked as a whim, or as part of a duty or personal goal', which is true. It's not deliberately misleading, but it's too emotionally manipulative.
"It's possible that moral alignment in this world is so different from my own that I'm not Evil here. I tried praying to Saint Peter for guidance, and I plan to visit a church and read your holy book in the next few days. Can someone here instruct me? Does Saint Peter have disciples?
In my world, the fundamental forces of Good and Evil, and Law and Chaos, were defined by the creator, who then set up a system where lawyers argue to convince a judge what afterlife each mortal soul is sent to. The results of those trials don't always line up with the mechanism of naturally-accrued alignment, which must be periodically updated to better match the opinions of the judges.
The original intent, as best I know, was that making people happy is Good and them sad is Evil. But faced with the overflowing creativity of the mortals and the lawyers arguing for them, the judges - and sometimes the creator Herself - added more and more complications.
Good came to mean healing the poor, putting up with abuse, diligently teaching your children your trade, injuring your children so they behave in the social role expected of them, fighting monsters, fighting Evil, making people do things against their will if they're things 'everyone' approves of and in particular things that strengthen the forces of Good, using certain psychoactive substances and rituals, giving people hope even if it hurts them, and some kinds of suicide.
Evil came to mean torture, social self-sufficiency, murder for any reason other than self-defence, diligently teaching your children your trade if it's a trade She doesn't like, making people do things against their will if they're controversial or strengthen the forces if Evil, any sort of business deal involving souls, giving people incentives if you like doing that too much, liking some people more than others, creating or employing or being some kinds of creatures, breaking people's will even if they're happier afterwards, and all the other kinds of suicide.
My god cares that people like themselves, without relying on others' opinions, even seriously spending resources to make themselves more awesome; that people follow comprehensive rules so that they never worry about whether someone likes them or not, because being liked wouldn't change the outcome; that people's lives are shaped by experts, rather than letting them blunder where their feelings take them; and that people are organized into hierarchies with clear, limited duties.
If you're worried about woe for Miss Hampson, I am confident that she will be more successful with this course of action than with any others I know of. I don't know her well enough to say whether she would be happier. Normally, I want my vassals to be happy, but Miss Hampson is not mine and probably never will be, so I can imagine her suffering emotionally in my shelter, surrounded by my people, with me unable to fix her.
If you're worried about woe more broadly, I think it's likely that her help building my shelter will cause more people to survive the cold, and with lives that they consider better than death. If you're worried about me gaining power and converting others to my Evil ways, yes that's exactly what I intend to do and it's quite understandable that you might object to that.
On the topic of Miss Hampson leaving this 'place of faith', it is important to me to encourage her relationship with her god, whether that's 'God', Jesus Christ, Saint Peter, or one of the other gods or lesser entities in this world."