Of course a sage kd would take a YR10 cf with a cleric kingdom if agreed. Emeriti was ready and planning to fight you after your post war, but it was you who decided against that and decided you instead needed to "kill" the #1 prov and make a bunch of drama rather than just take back the 380acres + free land from him and give him a cf.
Why would Emeriti warring your ally in YR3 stop them from warring you after in YR4? You could have sat stocking gc and pumping sci the whole time then fought Emeriti after their Pyro war before they could fully restock. Obviously it was BB that didn't want that so instead chose to deal break and wave Emeriti into their war.