I think a connection to the first games is the only kind of 'reveal' that would warrant the kind of day one discussion Swen is talking about. Whatever it might be. Maybe the artifact is a prison that the last bit of Bhaal essence our Bhaalspawn hid away, and "who do you dream of" is a pocket plane-esque specter of the Bhaalspawn.
Or it could be something something the Absolute is what! something. Ho hum
The Bhaalspawn is more about violence and murder rather than seduction, so I’m pretty sure the Dream-person isn’t related. Also, I’m pretty sure that canonically the last bits of Bhaal essence were sent back to the source when Abdel and Viekang took each other out in the Murder in Baldur’s Gate campaign. At least that is my understanding. Never actually played it.