Grindelwald was waiting for his followers in the same conference room they used in the first chapter, which saved us the expense of building a new set. Vinda and Credence were the first to arrive for the meeting.
"Vinda, what have you done to Aurelius?!" demanded Grindelwald when he saw Credence's mouth was gone.
"Trust me, this is an improvement," Vinda insisted. By the way, it turns out she later becomes Harry's owl Hedwig. This is canon now.
"Finite Incantatem!" said Grindelwald, raising his wand.
No sooner had Credence's mouth reappeared, it uttered the words, "I'd prefer to be called Credence, actually."
"Did you hear that?" asked Vinda. "The boy wants to be known by his filthy Muggle name!"
"Vinda," said Grindelwald in a warning tone, "we're not going to abuse this sensitive young lad the way he was abused by that horrid Muggle woman who cared for him in New York. We're here to make all his dreams come true. If you want to randomly torture someone, that's what Abernathy is for!"
"Speaking of which," said Credence, "I do have a new dream. I mean, in addition to finding out where I came from."
"What is it, my son?" asked Grindelwald, with a creepy smile that was supposed to look fatherly.
"I've realized that I don't want to just be lonely and confused," said Credence. "Instead, I want to sing songs about how lonely and confused I am."
"You mean like some kind of... musician?" asked Vinda in disgust.
"Yes, that's the word!" Credence agreed. "I want to be a musician now!"
"Then that's what I'll help you do," said Grindelwald through gritted teeth, his smile now looking very forced.
"After we find the Toenail of Icklibõgg," added Vinda, as the rest of the Death Eaters entered the room.