Visible crew/equipment: Right as Ella is downloading the brain-melting computer program, when we see Rachel cooking, it is possible to see crew members reflected in the pot on the stove.
Continuity mistake: Near the end of the episode, when Brian Dempsey is threatening to kill himself, the gun he is pointing at Olivia switches hands. He is holding the revolver under his chin with his right hand in closeups, but in shots of Olivia, he is pointing her gun at her with his left hand.
Answer: In the time line of Season 4, William Bell is trying to destroy both universes to create a new one, and he needs Olivia to power the collapse. So he helped her escape. But the real question is, if not in search of Peter, why Olivia has to travel to the alternate universe to be captured and replaced?
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