I must say this seems like a rather dishonorable way to treat your allies.
Haw! Shall I show you his post-war plans for his Croatian "allies"?
Especially allies who helped you in your own most recent war.
....I'm not sure when the last time he helped me was. He yoinked some of the Italian partition that OY wanted, but I don't think that counts as helping.
Allies? No. Military business partners, yes. KoM does not trade in loyalty, only in real-politik, and was in fact plotting against me up until the moment I offered him a better deal. All his other neighbours (OY,vR,Foels) he plotted simultaneously with and against, so I can then only presume in the same manner he also plotted against me during this time of cooperation. I fulfilled exactly my contractual obligations: keeping no less than 3 of the big boys out of his hair while he stabbed backs, I ask what more I could have done for him? And yes, I demanded my fair pay. The fact that he fell in his own snakepit is neither here nor there. Its just business, nothing personal.
If he wishes more heartfelt support, there is always conversion on the table.