I’m making a mod that matches the history of Japanese Sengoku and each county vassal, but I have a problem

ppq095

Recruit
Apr 11, 2020
1
0
The current progress is to make the administrative division in line with Japan at that time. For example, in the original game, tosa had only 3 provinces, while there were actually 7 provinces at that time, and they were held by 7 different clans.

-----------------------------------------------

In this game, I want to add an event:
1: A is the owner of a PROVINCE, a has z PROVINCE, and there is only one left z PROVINCE belongs to a

2: B is liege, A is vassal

3: c is the attacker who besieged z PROVINCE

----------------------------------------------

When there is only one province left in A, when this PROVICE is under siege, there is a chance to trigger the event:
-If the player is A: You can choose to force the player to leave B's family and join C without being destroyed

-If A is ai, you can give ai a chance to continue to face the siege, or a chance to leave B's family and join C without being destroyed

--------------------------------------
This situation is more in line with the condition of the ear of sengoku in Japan. At that time, the subordinate behaviors of clans in various parts of Japan for the survival of their own clans were surrendered to stronger clans.

--------------------------------------

According to the above conditions, how should the event be written?