What actually happened the night of the Revival?
- Aaron is shown in India researching the broken creek. In his office he claims creating it required a blood sacrifice.
- Em says that Jordan Borchardt was the original target for the blood sacrifice. Her father was shown drowning his sorrows due to guilt(?) and her mother apparently knows quite a bit about the ritual itself, implying that her parents volunteered her for the sacrifice.
- Dana's phone logs show Em and Aaron were texting/calling back and forth immediately before the event.
So Aaron spilled the beans about his plans and the location. Then a horrified Em interrupts after the ritual but before the sacrifice and sends Aaron and the Borchardts packing somehow. Em gets back in her car after they leave but it breaks down on the bridge. She gets out, calls Aaron to berate him again, then gets murdered and dumped in the river. Her murderer completes the ritual. The extra life energy due to the change in sacrificial target sends the ritual haywire, resurrecting dozens of recently dead people in the Revival and leaving its intended target unaffected.
Or am I missing something?