This is the first quest of the game's fifth chapter. This entire quest is a cutscene - you don't have to do anything - it will start and end automatically right after your return to your camp from the Scholastone Institute.
Hernand is bustling with excitement over the harvest festival. Meet Marius before heading into town.
A messenger will arrive at the camp to inform you that a delegation from Demeniss is coming to the festival.
You will decide that Damiana - being a fugitive from Demenis - should know about this, but unfortunately, she is not in the camp.
Marquis Serkis announced the arrival of a Demenissian delegation and extended a banquet invitation to the Greymanes. This news poses a grave threat to Damiane, who is a Demenissian in hiding. However, she is currently nowhere to be found within the camp.