impina

Unfortunately exploring code with nearinfinity is the best I can do, I am not familiar with this language whatsoever ><.

Thanks for your quick reply though. Hopefully someone who can help, finds this in the future.

In the meantime, maybe have a dialogue pop up where edwin/dekkie indignantly demands whether PCNAME is attacking them on purpose or not, to which you can say it was a mistake / outright declare war?

The exact quote is: 

Charname "you have just made a very bad mistake."

its "@98 = ~<CHARNAME>, you have just made a very bad mistake.~"  from erdekaras.tra

It feels like I selected something antagonistic, but i didn't.

UPDATE: I used a lot of AOE in the fight, and a cacofiend [playing insanity mode]. I can't promise that I hadn't accidentally cast some hostile spell on him by mistake though, since there were so many enemies all clustered about.

I went back and looked at the code, looks like I somehow damaged Edwin mid fight and triggered "Edwattpc" variable. I deleted the variable using EEkeeper and the issue didn't recur. I also played this on story mode and cast no AOE, just melee'd them to death and didn't have any issues. 

P.S. I'm not sure Edwattpc trigger is a good idea. friendly fire happens a lot in this game. This  betrayal should be an active dialogue choice instead of accidental poison tick from cloudkill or something. Also I have my rod of resurrection for my eddie if he does kick the bucket temporarily...