Originally Posted by michaeltscott
I'm pretty sure that she did cross over. I'm not sure why she did it (obviously not to retrieve Peter), but we do know that Fauxlivia did her infiltration thing--Walter had a major attitude about it when Fauxlivia came to the lab to retrieve red-Astrid. I suppose that it's possible that they abducted Olivia some other way and replaced her with Fauxlivia, but the replacement definitely happened--in that episode Walter gives her back all of the stuff she left behind, including a little case that Walter had assumed was a spy device which turned out to be a mint dispenser.
Yes... in this timeline Olivia was still replaced... but they didn't take her back to the red universe. They just held her captive somewhere.
In the original timeline they captured Olivia on the other side (so technically they didn't transport her over then either) and Olivia got home by herself.
But there was no instance (that they've mentioned so far) of Olivia and company going over to the other side like they did in season 2... and especially not one that required Bell to help them get home and sacrificing himself in the process.
Basically, we haven't been told a LOT of what changed... including whether or not Bell is alive or dead or what in the new timeline. Since they haven't shown/told us... they could easily pull him out of their hat and especially IF they could convince Nimoy to come back since he did do an appearance (sort of) on Big Bang Theory recently... he hasn't "completely" retired from acting as was the original plan apparently.