That a character, who died in a previous book, appears living in the next book, namely in a scene before the death. Would make the timeline for normal readers even more confusing.

And as said, BS's statement that "Graendal's name" is mentioned a few times in ToM, indicates that others will talk/think about Graendal, her plans & death (e.g. Moridin, SH, maybe Aran'gar). This makes more sense than another PoV from Graendal before her death, especially since ToM apparently won't deal much with Rand's plotline, and Graendal was in Rand's plotline after all.

Besides, e.g. Sammael's death in ACoS was a bit disputed as well, but he also didn't get a PoV from before his death in PoD. No reason to believe this will be different in Graendal's case.