It's still problematic in that contradicts everything we know about stigmas and how they work. Never mind the fact that anything the dominions say is never really the whole truth and it could all be a coverup or secret mission among many other things (
yeah we read that) but even taking what is said at face value makes what happened unprecedented and strange. Gaius may or may not have had a potential stigma, it's never confirmed if that's what Barkhorn's interest in him was or simply in his preternatural abilities in sensing things like higher elements that they're trained to sense among many other people with special abilities can, and since his duty was to give them sunday school anyway it's an opportunity to, at the very least, groom a potential squire if nothing else. But ultimately the problem boils down to this: Barkhorn gave Gaius his stigma (unprecedented), Gaius claims it's the same stigma Barkhorn had and hence the same seat was gifted to him, which means he couldn't have had his own potential stigma because what we know about stigmas is: There's only 12, there's no dupes, and there weren't any open seats in the dominion as far as I remember. There's also nothing that truly qualifies as enough of a trauma, or a relic, to fulfill the known conditions to stigmatize anyway. But he also says that him becoming a dominion wasn't a choice or forced on him, he says specifically it was a
"gamble.
" There's more to the story that isn't said, and that's why it's weird and unprecedented. But this doesn't preclude anything about Rufina either since A) if it requires the death of a dominion to transfer a stigma, the church is not gonna just go and kill one just to promote someone else, and/or B) requires a natural affinity for things like the higher elements that Gaius had.
Either way, it's all around a strange turn of events that never gets cleared up, which just makes it seem like it's actually the truth, that it was indeed transferred and that's that. *shrug*