How about an out of the box feature?
Go to the database.
Make a Troops out of the enemies you want to take part in the battle.
Use the eventing system inside the Troops, to make the dialogue.
Using THAT troops as Battle, will include the eventing.
Edit:
A Skill can use a Common Event.
The Common Event can trigger a Switch that can be set as a condition for the eventing.
You MUST start the battle though by stetting that switch to OFF first (because the skill might have already set it ON from previous battles.
Just throwing an idea how to set things up.