My first instinct was that Anna is an otherworlder as well, but I think she's just sharp enough to realize there's unnatural knowledge going on.
If that's the case, then...hmm. Just where is this going? Are they gonna be allies? I hope that'll be the case.
Once again, the duke trio conspiring for such a petty reason is...Like, this is totally them looking for an excuse to rebel now, right? Anything our MC does is just going to be the pretense, and a civil war was basically inevitable. I feel like we should just snuff them out while they're not up in arms.