The Witness isn’t dealt with in the raid, the raid is more so the bulk of the damage while the eighth mission after the Worlds First Clear will be the finale. After that there’s plenty of loose threads, like the Fanatic and Scorn, Torobatl and Xivu Arath, the Psion rebels, [spoiler]veilified Maya Sundaresh who is undoubtedly the Episode antagonist[/spoiler], plenty of story threads to pull on.