Ah yes, here we have the undenialable proof. Now let us watch how they will deny it
Also it was brought up that Jaina could have assissted on Darkshore. This is false. Jaina was at this point in time on Kul'Tiras and then near Theramore to raise her dad's ship.
It is clearly implied that she learned of the genocide at Teldrassil during the Siege of the Undercity, just look at her face when Anduin mentions it to Sylvanas. She did not have a clue. So she could not help sooner. Something we can blame Khadgar for, who pushed her away from the Kirin Tor. She told them that the Horde could not be trusted and she was proven right yet again.
Wonder if Khadgar ever apologized to her before locking himself in Karazhan and refusing to help his people against a psychopathic Banshee.
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The problem with this stance is that you think these things happen in what little time has passed since Sylvanas has poofed away. Out of game month and nearly a year has passed since that time, but then we had to deal with N'zoth and shortly afterwards (ingame) the Scourge suddenly attacked again. There was just not a lot of time to engage in politicking and these kinds of negotiations can take years.
First order of buisness was stopping to kill each other but the reparation is not forgotten. Remember, Thrall
swore to bring Tyrande the head of the Banshee, that is one thing, releasing Shaw from prison and giving him Sira as a gift to the Alliance is another. But now we first need to stop said Banshee from ending reality then we can have negotiations again.