Alright then. You guys bought the stealth armour. Indigo equipped the ring of invisibility, while Jack replaced his military gear with the stealth armour.

Jack and Indigo leave the town. Both are invisible to people besides themselves, and slowly walk to the area where the shield is. Jack, being a T-800 and all, is smart enough to fire a rocket at the Trocasian position, and slowly walks towards the shield. Indigo manages to use the distraction Jack created to grab the shield system(which looks like a highly advanced grenade), put it in his pocket, and run back to the city along with Jack. When they arrive, they discover that the city is under attack by the Trocasians. Jack and Indigo manage to cut through a section of the enemy enough to enter the town and rejoin their comrades.

I would suggest that you put yourselves to good use. You have weapons and you know how to use them, and there are some Resistance members who don't have weapons. Just tello me what you want to do, and I'll type it out.