lolface -“he is a BIG skeptic and hates all things mystical,”
Sorry, I’m a bigger skeptic. In my mind, it was his Neshoma talking to him, not the dead person. He was alone -he saw a yid who looked like his Zaida and sat down. He probably nodded off for a few and had this dream. He might not even realize it was a dream. But the resemblance to his Zaida triggered his Neshoma to wake up. The reason I think, it was a dream is because if it was the Nifter, why would 1. he have contact with his Zaida? Remember the Neshoma has not gone up to Shomayim at this point. 2. Why give Mussar on just Tiffilin and Kaddish -What about all the Mitzvos?