A mind not filled with desires
That doesn’t sound at all like the reaction of a guilty person, so that narrows it down to Victoria being innocent of arson or her being a canny callous liar with no tells.
“I’ve only seen one pamphlet claiming it. It had a lot of sensational claims. Let’s see… it claimed the Calistrian Whore Valia Wain led a mob, started fires, killed a Select of Iomedae… and she’s already been arrested, quartered, and even maledicted… and Iomedae herself appeared to carry out the punishment. In other words, complete fantastical nonsense. I may be missing some more nonsense details, even as short and sensational as the pamphlets was. Anyway even if the government wasn’t trying at being Good now, I don’t think they would tolerate a cleric of an Evil God to get maledictions cast.”
“My default assumption is pamphlets aren’t true, even if sometimes have some tiny grain of truth. I was wondering if that pamphlet confused you and Valia somehow, but even though you are a Calistrian I take it from other things you’ve said you aren’t a prostitute, so even allowing for that confusion the pamphlet is still complete garbage.”
Thea takes a moment to look for any tell in Victoria.
On to more important topics… the pamphlets Victoria favors makes sense of her and some of them even seem reasonable. Thea notes the titles so she can find the copies she already has in her library back at the monastery.