Hi there
Nobody is asking you to do the work other people are supposed to do. Its just that bugs are handled by the appointed team, which needs to be notified.
Anyway, regarding your question: Just like there is the risk for your army to run when they have low morale, there is also a chance that they dont. And if your army reached zero morale (which i`m not sure its showing correct in the visual report) at the same time when the defenders army has given up on the battle, then you would win.
Cheers