Um... Why would Yulia poison herself?!?
Ok solider plan this time. I agree an incendiary grenade either dropped by Yulia or thrown close to her is a good play... Hopefully her cloths survive as they are mostly on the floor.
Yulia get to the team quick! Energize yourself since you can see yourself, undermine the 2 bats if you can, otherwise just run to the scream! The grenade should give a bit of light to help maybe, just be ready as it may be bright.
On the run drink a mana potion and once together energize Cherchiel and Isailia. Goma usually has the horn, so Cherchiel beat the shit out of that bat holding her and then Goma sound the horn!
If the bat with Goma attempts to flee with her, Isailia immediately throw a grenade at the bat to ground it. We can heal Goma, but if she gets to far away that may be it for her. Hell, throw two if need be, make sure everyone groups up!
Once together, get your backs to the wall and fight like we did before with Cherchiel and Isailia up front.