What clues in the book led you to guess the true identity of the killer? (bookbrowse.com)
Through a series of decisions and quick time events, players are able to dictate branching parts of the narrative, discover the true identity of the killer, and determine the fate of certain characters. (thekoalition.com)
That background information sounds like it's spoiling the ending, but Pearce keeps the identity of the killer ambiguous right up to and perhaps even at the end, depending on how one reads the final scene. (hollywoodreporter.com)