In my last game I noticed something strange.

This is the situation: Me, custom race. I am the most powerfull civ, Korkx are second. I have an alliance with every other race, except with the Korkx and the Yor so I’m going for the diplomatic victory.
With the Yor I have trade relations and their demeanor towards me is ‘warm’.
With the Korkx I’m at war. This is the only war at the moment as all other races have trade relations with each other.

Since it’s the endgame I wanted to speed up the Korkx’s downfall by having my allies attack them.
The only thing is: I can’t ask them to attack (except for the Drengin???)
When I ask to attack an other civ I can choose every civ but the Korkx. They simply won’t show up in the list where you choose which civ is to be attacked.
Exept for the Drengin, but they won’t attack for a reasonable price.

I never noticed this before because this is the first time I pursue a diplomatic victory and I never before tried to ask for a civ to attack someone.

So, what am I doing wrong? Why can’t I ask my allies to attack everyone but my enemy?

Thanks