The Shadow Wars (Siege missions) stuck att 88%

[Dog Viridi]

While I was at the 2nd stage of The Shadow Wars, 8 captains banded together on a single cap point and unsurprisingly killed me. I hit alt+f4 during the execution but the fort was already lost when I loaded back in... So I rescued my captains, re-captured it and went forward with the quest.

Then I finished the last defense and... Nothing. No cutscene and the quest was "complete" at 88%. Is there anything I can do to fix this? I don't want 4 hours to be lost for nothing.