It wouldn't make sense if Vogel is the killer. She received a text message from an unknown person that said, "LOOK OUTSIDE" before finding the brains in the gift boxes. They didn't fingerprint the gift boxes because they know the killer would be smarter than to leave fingerprints.
What if Hannah McKay is the killer? She escaped prison at the end of last season.
I never said it was. I just know that any humane person considering an abortion would likely have a change of heart if they saw the "thing" growing inside of them via an ultrasound.