is attack on titan (shingeki no kyojin) episode 64 filler?

Backstage, Willy Tybur is informed that it is almost time for his theater production to begin. He is greeted by Kiyomi Azumabito and her bodyguards, and comments that he must look terrible due to his stage fright, but she says that he looks courageous and her entire clan is aware of his bravery.

She wishes him luck, which he appreciates. In a dimly lit basement, Eren Jaeger tells Reiner Braun to sit down.

Eren mentions that they can hear the stage very well from where they are, even though the building is located behind the stage.