is one piece episode 344 filler?

The zombie soldiers march through the forest carrying a large orb. Meanwhile in Hogback's lab, Nami learns the truth about how Hogback was making the zombies.

She also tells of how Cindry died ten years prior. Having been found out, Hogback orders Cindry and Ryuma to kill the group.

Ryuma then walks into the lab laughing like Brook and admiring Nami even without his eyes. He almost gets to glare at Nami's panties but is denied.

The navigator begins to wonder about Brook's personality being replicated by the samurai. Ryuma was once from the kingdom of Wano.