Ok, so here is the story:

Basically, there is this Big Bad Evil McEvil "spellcaster" in this town that is surrounded in an Anti-Magic Field (AMF). Our party needs to defeat/capture/kill him because he's a higher member of some secret plot to overthrow our home city of Silver trees and sunshine. Now, two sessions ago we were told that the spellcaster can cast within the AMF, as a matter of fact we saw him casting from a distance away well before we entered the city. We met a resistance that has helped us enter the city and now we're inside of an AMF with very few ways out.

The party was split and half of us found out, from a most-likely reliable source, that apparently the AMF uses a material focus and will go down as soon as we can destroy it. Of course, the focus is an innocent lady whose the wife of this poor one-armed guy who refused to not come with us into the city so that he can save his wife and daughter. As we kept getting information about the situation the more and more impossible it seemed to avoid killing this lady. I'm trying to play an ultra-good character but I don't think any decent wisdom (let alone high wisdom, which I have) character would commit suicide and condemn an entire city for the sake of one person. By the end of the session, despite it being a good one over all, I was a bit mad and asked the DM flat out if there was any chance we can save this lady or if he was going to shut down every idea I had (as a few of my idea were shot down already.)

He said there was.

So I would like to save her if possible. Below are the details.

Spoiler: Party composition
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All level 11, we level up rarely.
The following know about the lady being the focus of the spell:
-DMM: Quicken Wisdom Archer. Cleric level 8. (Good, this is me)
-Monk/Sorcerer (Lawful Neutral)
-TWF Favored Soul. Favored Soul level 9. Very sub optimal spell selection. (Good)

The following do not:
-Rogue (Chaotic Neutral I think)
-Wizard? Not sure, joined last session.
-Frenzy Barbarian Ubercharger (Died last session, will have a temp replacement, not sure on details.)


Spoiler: Details
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1) I do not have access to Revivify and Raise Dead yet.
2) Moving her, knocking her out, anything but killing her, will not remove the AMF. The AMF is not centered on her. (Honestly I hate this trope)
3) We work for a powerful guild that only loans us magic items before we go on quests. We currently have 23k Credit that we can use. I can get consumable materials in the future (ex. Diamond Dust for Raise dead) but that will drop my credit permanently (not sure by how much).
4) EXP is not used in this campaign, to do anything involving EXP we need to find EXP stones.
5) The ultra powerful guild will not resurrect her for us, they only resurrect guild members.
6) Round about plans have generally been prevented via railroading, so I don't know if we'll be able to leave the city and waste an entire day prepping. Otherwise I'd leave the city, use Substitute Domain, wait 24 hours, and do the Shrink Item anti-AMF head cone trick.
7) Apparently, while the party was split, the Frenzied Ubercharger blew up a lvl 16 Druid, meaning the DM doesn't play spellcasters that well, bc the Ubercharger isn't that great, he has a will save of +1 and no ways to overcome a lot of charging issues (obstacles, rough terrain, etc).
8) While I'm not sure about the Wizard player, the entire party is lower power than I am, and I don't consider myself that strong. I don't think the Wizard player has any plans vs the AMF bc he was freaking out when he heard about it.


Spoiler: My build personally
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-Ranger2/Monk1(Iregretthis)/CloisteredCleric3/ChurchInquisitor3/SacredExorcist1/Contemplative1
-DMM: Quicken and pre-reqs, Elf, Time, Undeath domains. Knowledge Devotion. Zen Archery and a Homebrew feat that gives me Wis to DMG.
-The DM has books limited to Core, Completes, ToB, and Spell Compendium.

Even under the AMF, with average Knowledge Devotion rolls and Wis to DMG and To-Hit I have +13 to hit and 1d8+11 damage with 3 attacks. Sadly, my build was pretty dependent of Quickening Magic buffs on myself for maximum pew-pew. The DM has started throwing homebrew-anti-cleric-archer stuff at me (arrows that do dmg based of my Wisdom score, an imp that auto-reflects arrows), last session I made sure to tone down my power because I didn't want to be disruptive (I did more buffing/healing less pew pew).


Now, my last option solutions are one of the following:
1) Fight the wizard guy solo and hope I win somehow with my massive saves and potions. If I die the guild just brings me back, I have a temporary backup character already made that will wreck this wizard (coincidence btw). The reason why I specify solo is because I don't want to get us all killed and if I lose the party will probably just drop the AMF via murder and then wreck the wizard guy.
2) Kill the lady after a conversation with her. Place her in my back of holding and swear to the Overdiety of the campaign himself to re-unite the family. Wait until I level up (I have a feeling it will be after this mission) and then permanently drop my Credit wealth by 5k in order to get the diamond dust to bring her back. I did some fancy math and found out if the guild makes me the reliquary symbol I want (for future borrowing), then odds are I will be barely weaker in the future. I'm already pretty strong (relatively) and I wouldn't mind being weakened. But I would still try to avoid this situation in any way possible.

But like I said, anything that will certainly work is appreciated. I've done a lot of DMing but this is the first live campaign I've played in, so I'm good at making dungeons, varying difficulty encounters, etc. But I'm bad at being creative as a player (I feel like), which is probably why my own players surprise me so much.

TLDR: How can I not kill an innocent person when she's the source of a city wide AMF?