It depends on the buff. I don't think defense up can be removed and it applies damage before it dispells, so advantage with 1 hit on it already cannot be dispelled by humbling blow, nor can defense up at any point (I think), and it can also be resisted. Since the damage is applied first, foresight cannot be dispelled by QG and a finishing blow will never dispell with QG (if you kill someone with humbling blow, it will never give offense up).
I have lately noticed this when facing Chiwe or Phasma. At time QGJ is able to remove the buff from them, but it does not add offence up for the team. It sure is not working as expected.
Nothing to do with defense up or any other reapply buff. I keep seeing this happen and he hits the character and it doesn't dispelled the buff or give the offense up. It also doesn't say the attack was blocked, dodged, etc. It just fails to work aside from the special damage. Only seeing it in GW but it's at least once a GW and it's not game breaking but it's still a bug that should be looked into. Thanks guys!
For example, hitting count dooku with advantage which should remove the buff from him, apply the buff to my team. It just hits him and there's no buff change.
Buffs that can have increased durations via their respective ability upgrade stop getting recognized by the buff-stripping abilities' mechanics once they've actually been upgraded to increase the duration.
This problem has been in-game for a while, and also applies to debuffs (and the debuff removing skills respectively). Recently, they patched it so that both IG-88's and Sideous's upgraded durations for heal immunity debuffs could finally get removed, so I think they're finally working towards getting the whole situation remedied for both buffs and debuffs (and their respective skills intended to remove or cleanse them).
Replies
For example, hitting count dooku with advantage which should remove the buff from him, apply the buff to my team. It just hits him and there's no buff change.
This problem has been in-game for a while, and also applies to debuffs (and the debuff removing skills respectively). Recently, they patched it so that both IG-88's and Sideous's upgraded durations for heal immunity debuffs could finally get removed, so I think they're finally working towards getting the whole situation remedied for both buffs and debuffs (and their respective skills intended to remove or cleanse them).