I have to agree with the original poster here. The faction/attitude shifts that are happening in relation to this event make zero sense. It's like the person who assigned these attitude penalty values paid absolutely no attention to the context of the conversation taking place.
Problem #1: You lose attitude standing with Lohse for trying to stop her, even though she wants to be stopped before anyone is hurt (she literally cries at the end for almost having hurt someone).
Problem #2: Your entire party loses attitude standing with the entire cave community, even if your party chooses to stand with the cave community to stop Lohse. This is doubly ridiculous, by the way, when you consider the ongoing problem of co-op players not being properly rewarded with positive attitude adjustments for good deeds because they didn't talk to NPC-X before their friend did.
Problem #3: Even if your party chooses to stand with the cave community to stop Lohse, your party still performs attacks of opportunity on any cave community members that move by. And, they are also targeted by cave community members instead of being flagged as their allies.
Problem #4: Lohse loses attitude standing with the cave community, even though the leader repeatedly tells Lohse it's not her fault, that she is aware of the danger lurking inside of her. She clearly sympathizes with Lohse and wants to help her, yet oddly her attitude sinks into the toilet.
Again, it's like the developer who assigned these attitude penalty values paid absolutely no attention to the context of the conversation taking place (or didn't understand it).