Factual error: Wanda's father opens his briefcase of DVDs and one of them is Malcolm in the Middle. But the bomb that killed him fell in 1999, and Malcolm in the Middle didn't start airing until 2000.
Factual error: Pete died in 1984. Yet mentions the movie 'Ghost' with Patrick Swayze which released in 1990.
Suggested correction: It is established that the ghosts have watched television, listened to the radio, smelled pizza/pepperoni, etc. It's not impossible that Pete saw Ghost on TV.
While they do watch television now, it's unlikely that Sophie watched "Ghost" and that Pete saw it alone. The reply from others was "you know we don't know what that is" and he said "oh, right the movie thing." Which was a call back to earlier when Trevor was trying to explain who Tara Reid was and the older ghosts had a hard time knowing or remembering what a movie was.
Factual error: When Alina stands outside of the door to the banquet hall, waiting to demonstrate her power to the king and queen, there is a modern electronic occupancy sensor on the wall behind her.