This seems like something she may have done as a test of sorts. To see how we would react and if she should reset us or not.

[He says it with a sneer, not pleased that she seemed to view the prospect of killing them all as some sort of game.]

I went into the forest with a small group for about a week and there are definitely things in there that are not making themselves known. A large howling creature was keeping pace with us but we never saw it. And one night there was the sound of a woman singing that came from the river.