There already is a knockout mechanic, it's just not working quite properly yet.
I have written this badly here, sorry. I meant exactly what you have said; same thing was written by me in other thread, linked above.
Knocked out characters bug the quests, aren't registered in them or just get slaughtered by nearby npcs. There is little interaction with them afterwards.
I have a feeling though that Minthara might be the ''hell no, I'm not working with you, kill me or sod off.'' type.