If you do end up playing as Durge Fylimar, my recommendation is to save every time you want to click on the Long Rest button after getting Karlach and Wyll into the camp, as that seems to be the trigger when Alfira will come to the camp. Then just reload whenever this scene occurs and do any of the two metagaming techniques.
Sucks because I would prefer a proper legit roleplaying way to save Alfira and not kill anyone, but they absolutely do not give the player any legit choice on the matter. Irks me so much that two desirable outcomes are locked away through metagaming and that one of them even has dialogue for not killing anybody that night.
