Some people believe that the rumors were wrongly started by the departure of Cook from the show due to her maternity leave, as they saw that as an opportunity for the writers to take her character out of the equation while allowing her to take her maternity leave in peace.
Now that she’s back on the screen and she’s apparently found a way to balance her newborn with her work, this doesn’t make much sense anymore, and if the rumors about her permanent departure really did start due to her newborn, then people might want to give them a rest at this point.
In any case, A. J. Cook seemed as excited as we would expect her to be, and she’s apparently very happy to be getting back on the show. We don’t know if she’s aware of the full plot arc of her character yet, but if she knew that her death was coming up, then maybe she wouldn’t be so cheery in the first place.
We’ll have to wait and see, but we’re confident that the writers of the show have something exciting planned for her in any case. Even if she’s eventually killed off, we expect that this would happen in an appropriate way and not in a way that would traumatize viewers and disappoint them.