is attack on titan (shingeki no kyojin) episode 77 filler?

Armin Arlelt asks Mikasa Ackermann if she wants to help Eren Jaeger and she admits she does, but is concerned that it is simply because it is in her blood. However Armin thinks both the story of the Ackermann lineage and Eren's agreement with the euthanization plan are a lie because it does not sound like something he would believe in.

Jean Kirschtein agrees it is out of character, but does not find it that unbelievable, and Conny Springer demands to know why Eren does not oppose Zeke Jaeger and Yelena if he disagrees with them. Armin insists that it is because Eren does not have to.