What, no FFXIII-2 thread? POTENTIAL SPOILERS

In regards to Alyssa:

 Spoiler

She was given the fake fragment by Caius because she was afraid that if Serah and Noel change the timeline, then she (at that time) would cease to exist. She says so just as they enter the Historia Crux, she says sorry, and goodbye

I got that but her motive didn't make any sense. But then I read in a fragment from Augusta that said...

 Spoiler

She actually did die during the purge, not her friend. So she was afraid that by fixing the "true history" that things would go back to the way the were and that she would be dead again. Caius must've played on that fear.