If Graendal died in the end of TGS, it would be completely untypical and confusing for the series, to bring a character who died back in a previous scene. BS also just said that Graendal will be "mentioned" in the book. What BS obviously meant with the overlapping timelines is that he will show us what happened e.g. in Perrin's or Mat's timelines, which aren't at advanced as Rand's (and Graendal's) or Egwene's timeline.

It's also wrong that Graendal and Aran'gar have a close alliance. They just call it an "association", which apparently means that they exchange some informations once in a while, not closely working together. Aran'gar e.g. still doesn't know where Graendal's lair is in the beginning of TGS, as Graendal tells.



It doesn't make much sense, considering that both, Aran'gar & Mesaana, are basically working together to unstable the AS. This is also supervised by Moridin and likely SH. That saidin was undetected to kill the AS was rather wanted to suggest that Rand and the Asha'man are behind it to spoil any talks.



Aran'gar already knew that Mesaana is in the WT. In TGS, prologue, Graendal apparently didn't know who Mesaana is exactly. Considering that she had other more urgent tasks regarding Rand on her mind now, it's unlikely that she cared about Mesaana's identity at all.



Indeed.