Hello,
As you can see in the original bug report the player notes that it still assists from the spy's special which is what happens at 1:01.
At 5:12 that is not the same vulture droid, that is one summoned by the Malevolence not the one summoned by the last paragraph of the "Swarming Terror" unique as mentioned in the bug report and in the videos title and description.
We are talking about the vulture droid that spawns after the death of the players vulture droid because of the "Swarming Terror" unique. It does not assist in attacking enemies that have buzz droids except when called to assist by an allies special ability such as the Spy's "Surprise Shot" ability and Soldier's "Separatist Assault." As you can see in that video not once did it assist due to an ally attacking an enemy that had buzz droids. While we respect that it is a % chance of assisting the fact that it hasn't assisted at all since the update while the Malevolence spawned Vultures have would indicate that there is a bug.