Alright, rolling time. Let's start with the Martial Actions.
So, our first "warband" is actually a group of human hunting slaves with 2 Dark Elf masters. Evidently, the Elves were leery of just randomly sending in another warband to be slaughtered, and wanted to scout things out a bit more with some expendable units. It's a good thing you're taking prisoners then, and that you yourself were thrown into the ring, because you won't need to worry about coordinating with anyone else.
In this case, there is only the Size 1 group of slaves, and normally they would be Quality 0 due to not being willing military units, but the -1 from the cloaking field has actually pushed them into the negatives (might change this in the future so that there's a minimum, but I didn't think about it when designing these fights so you'll get it anyway.) And with a mostly human group with little-to-no weapons, that's just Might 0. So with Size 1 and Quality -1, that's actually a DC of 0. Still going to roll for it, to see if Sango is wounded from the fight, but I doubt it will be much of a problem. With Gwai's +12 and Sango's own Combat bonus of +16, that's a total of +28, more than enough to push him over the threshold of not being hurt. Well, -20 from taking prisoners as well to just +8, but that's fine.
Roll bonus: 12 (Gwai's Martial) + 16 (Sango's Combat) - 20 (Taking Prisoners) = +8
Result: 37 + 8 = 45, Success! Sango is able to disarm the Dark Elf taskmasters and their slaves, and after seeing how this golden glowing man is invulnerable, the slaves willingly surrendered!
Next is our second warband, which is... well, it's a ship. It's a ship full of Black Ark Corsairs (thankfully without Black Ark in tow). It's a major threat, especially since it can bombard from a distance... just a slight problem. It can't find New Uluiru from a distance. So, they get close to the shore, hoping that will help, and even that doesn't help them. So, they send their units onto land via rowboats, and its on that shore where the Eidolon Army catches them off-guard. You see, your scouts were able to catch a large ship coming close to where your homestead was located, and that gave Gwai the time he needed to build up his army, traveling alongside Flaris to surround this privateers.
The Corsairs are a Size 3 Army of Quality 2 (maybe should have been 1 now that I thought about, but I already determined the stats ahead of time, so oh well), reduced by 1 due to the field to Quality 1. They have Might 1. That means a total of DC 50 to beat.
The Eidolon Army outnumbers them by 2 (+20), and are the same Quality. With Flaris in tow, their Might is increased by 1 to 2, meaning that they have more Might than the elves (+10). With Gwai's bonus (+12) and Flaris' leadership (+12), that adds up to a total of +54, which will be enough to guarantee a victory barring any crit fails.
Roll bonus: 12 (Gwai's Martial) + 12 (Flaris' Martial) + 20 (Outnumber) + 10 (Might) = +54
Result: 8 + 54 = 62, Success! The Eidolon Army take most of the hits, and Flaris only suffers minor injuries, not enough to stop him from being used next turn.
This was supposed to be a difficult fight, and I guess it was. Unfortunately, the galleon decided to turn around when the soldiers it carried died, BUT the rowboats at least are fine! That will help with any water actions close to shore in the future.
And now our third Martial Action with raising the walls. Nokun is being used here because of her charm allowing her to make earthen walls instead of having to rely on Sorcery. Her Martial bonus of +10 combines with the charm bonus of +10 to make +20. Combine that with Gwai's Martial of +12, that becomes +32. (I debated whether non-Sorcerers can provide benefits to Workings, but decided that it would count as "expert advice" and so just kept the bonuses as is. Plus, it would be a jerk move to spring that on you guys without prior warning). That should be enough to guarantee the 2nd threshold, barring any Crit fails.
Roll bonus: 12 (Gwai's Martial) + 10 (Nokun Martial) + 10 (Earthen Wall Bonus) = +32
Result: 65 + 32 = 97, Notable Success on top of making the 3rd threshold! In this case, the walls are likely thick enough to have soldiers patrolling on top of them, giving you a convenient way to spy things from afar. On top of the other benefits that really thick walls provide.