As we know in the movie with Robin Williams Alan was the one who found the game but what was curious is why choose Alan of all people will if you look at the state Alan town was in shows that Jumanji chose to do this not just because alan wanted to stop playing the game but because one Alan was in the game his father would sacrifice everything to find his son whic as we know because the shoe factory represents a huge percentage of Alan town economy left it in a depression that allowed the games challenges like the monkeys or van pelt to go around without anything to stop them like think of it hunter using a assault rifle in a department store with no police to stop him du to the low budget caused by the depression and the monkeys taking over the police station

Shows that Jumanji planned all this from the beginning it just needed to attract a person like Alan to it then trap him inside it’s structure as a means to set events into motion