I do think turning over the vat was a good idea, though. The cursing? Probably not so much. Honestly, I have no idea what your curse actually does, but we have more enemies inside the walls as well.
Annoying that we failed to spoil the attack on the west tower. Hopefully you'll guys make your saves, somehow, otherwise this is going to hurt a lot.
Once we're through the wall, we'll have 3 barricades to work through. How many successes do we need to get the gate down? I have a feeling we need only one more, so it may be enough to go at it with a crowbar this round with some luck.
If Fortune can hold her action, she can blast another group of kobolds once the gate go down. Alternatively, she'll just aid the ram and we'll worry about the barricades next round.