Two problems with that.
1. Perdan and Caligus already warmed realms not to harbor Ibby leadership or their kin.
2. Fontanese nobles admitted in public that some Sirion lords were funding Fontan and supplying knights with troops, breaking the 1 vs. 1 war.
Well obviously they want to say Sirionite lords are funding them. If Perdan accuses Sirion of this and somehow make Sirion gets involve in this mess, they might have higher chance of surviving
