You're war declaration message didn't say anything about Coralynth. It said "What we seek is a denunciation of the acts taken thus far by Sorraine and Coralynth, and oaths sworn that such acts will never occur again." No further explanation.
But really, it's pointless. This should have been the safest, most bland, inoffensive war that anyone could have dreamed up. A nice little test of FEI in the post imperial era. And it failed.