Sleuthing is probably not the right word for what Freya is doing at the beginning. She doesn't really have suspicions when she goes to Byrne Hall; she has the incredibly vague sense that she might find Answers, but Answers might mean either more information about Stella's death (at this point she has no suspicion Stella might have been murdered) or conversely a path forward in her own life, which more or less got stuck when Stella died.

And an incredibly intense love affair with Corey is (at least for a while) an Answer to that second question. It's only as the intensity fades and weirdnesses start adding up that Freya starts to realize that maybe there are Answers of the first sort here.