2/3
First I thought the bug could be caused by not eliminating all the sleeping lizars, muguls, and quilboars that you meet on the way to the gateway (except the ones surrounding the gateway). It seemed to work at the beginning of the mission, but they eventually got stuck again. Tried it multiple times.
Second, I thought maybe the bug would be fixed if I killed Garrosh and his troops moving back and forth between the base and Waygate, but after they respawned they still got stuck.
Thirdly, due to the position of their barracks, I saw that there was very little room for Garrosh and his forces to navigate around their base. It seems like their fortress is the default "retreat" point, and since the barracks are placed very close by there is very little room. I thought by destroying the barracks, maybe they would be able to walk around more freely and no longer be stuck, but it still didn't work.
the wrath of the lich king
memories