No, you can easily pass an Insight check to find the trap door to Mol’s hideout behind Doni, no need to turn into a mouse or anything. So it actually is quite easy to stumble upon her. That being said, it seems like she will always be hostile unless you have saved some of the kids first. And that kind of seems in character for her. You stumbled into her hideout, which you were never supposed to find because it was hidden. So she’s being dramatic and getting people to kill you. Seems in character to me. So I didn’t personally interpret it as a bug.