How to get the 5th copy of the joint recital?

by Farming (quest drop)

Joint Recital drops in the high difficulty nodes. The harder it is, the higher the chance that the CE will drop.
That abysmal low chance of 2% in Dantes is trivialized when you farm there for petals.
I got 12 copies now, excluding the ones from the shop.

Spam the patels node until you get one

I got it by chance doing one of the tournament matches. You'll have to play until you get it, I'm afraid.