Since I believe it can't hurt any IC things anymore and Caligus obviously prefers to die anyway the first terms (in short form) were these (all information is here OOC of course):
Caligus joins SA and give Fallangard MoI and Leibo (back).
Caligus quits the alliance with Sirion and joins again the southern bloc as equal partner.
Caligus gets Duchy of Krimml and Karbala in the future war with Sirion, and during this it would have given the Duchy of Hamadan to Fallangard to restore that former Kingdom completely.
All in all Caligus would have had in the long run more gold and one more city, along with a stronger alliance.
Terms got rejected since Caligus didn't want to end the alliance with Sirion.
War started. Caligus surrendered with new King, new terms were:
Caligus joins SA and drops the claims on the Fallangard regions (Hamadan had joined by then).
Caligus quits the alliance with Sirion and joins again the southern bloc as equal partner.
Caligus gets Duchy of Karbala in the future war with Sirion.
So, basically same terms, only Krimml got deleted, Caligus would have had lost one City and got another one, but still more gold, and a stronger alliance.
Terms got rejected, new Caligan King said that these terms were designed to kill Caligus (!).
Nothing more to say, everyone can make his own opinion on these terms.
For me personally, only a Sirionite puppet or a realm that has miserable diplomacy skill would reject such offers.
Especially when the current status could have been anticipated easily before.
At least we have a good war and more glory for the allied realms.
Sadly thing is that an old realm must most probably die.