Corrected entry: At the end of the film Alan wins the game and all is reversed, Alan returns to the moment he first played the game with Sarah and he's a little boy again. So if all was reversed as if it never happened why does his shack still exist years later in the 2017 film?
Corrected entry: When Allan meets Carl for the first time after coming out of the game, he asks what year it is, and Judy reminds him it is 1995. The badge on Carl's uniform states he has been serving in the police since 1974. The same day Allan gets sucked into the game, Carl is working at Parrish Shoes, not for the police. If this had been twenty six years prior to the events of the film, Carl would have been serving since 1969, not 1974.
Correction: 1974 to 1995 is 21 years. Alan disappeared in 1969 and Carl started working for the police 5 years after Alan disappeared.
Just because Carl was fired in 1969 doesn't mean he immediately went into law enforcement. Plus, he likely would have had to join a police academy first to get training before joining the local police department.
Correction: When Allen hears it's 1995, he says to himself "26 years"? He meant since he got sucked up in the board game until today. I don't think 1974 or Carl's badge had anything to do with Allen's comment here.
Corrected entry: Not everything in Jumanji goes back into the game at the end. We see the vines don't get sucked in, and neither do the spiders, bats, mosquitoes, alligator, or lion.
Correction: They do go back into the game, even though it's not shown. Because Alan and Sarah are back in 1969 at the end of the movie and Alan's house is normal, so the spiders, lion, etc. did go back.
Correction: There's also a closeup of Alan and Sarah holding each other as well as the black marble pulling everything into the game the entire time so even if we don't see it, it's still happening.
Other mistake: Alan's dice rolls throughout the movie does not add up to the 33 steps needed to win the game. The four paths vary from 32-35 steps to win. Alan rolls a 5, Then his next roll isn't visible but the location of the elephant, when Robin Williams returns after being hunted by Van Pelt, is square 9, making his roll a 4 (the dice shows 3 but they aren't reliable since they could've shifted in the commotion). His next roll is a 7 and the winning roll is a 3 for a total of 19. Even if we allow his second (questionable) roll to score 11 it still only lands him on 26. Alan never rolls a bonus roll. And no, shortcuts across the board weren't used since Alan's elephant finishes its original path when it crosses into Jumanji. Furthermore, statements made by the cast that they only need a certain roll to win the game are pretty much all inaccurate if you count their rolls and steps along their path.
Suggested correction: It's possible that where the paths cross don't count as "spaces" since two players can't be on the same path. Meaning each path is only 26 spaces (including the final Jumanji space). If we do count Alan's 2nd roll as 11 then he won in the required amount of spaces. The only two that are actually inaccurate are when Peter stated he was 10 spaces away when he cheated (he would have been 19 spaces away) and Sarah being 12 spaces away when she only rolled a 3.
Character mistake: When young Alan is talking young Sarah, he says that he found a board game at the factory. Alan didn't find the game at the factory. He found the game across from the factory at a construction site.
Suggested correction: The construction might very well be part of the factory, a new factory building for example.
The sign at the construction site said it was an "Executive Office Annex" that they were building.
Even though the sign said it was an Annex, construction was still being done outside of the main factory where Alan found the game. Not inside of the main factory itself.
Other mistake: Judy tells Sarah, "You can win if you roll a 12." She rolls 3, meaning she would need a nine to win. When trapped in the floor, she is told she needs a 7 to win. But that is not correct. If I count correctly, you need 32 spots to win. I don't know if any get 32 or more.
Suggested correction: There are cross sections on the board. Meaning probably, if they land on one, the pawn will go in a different direction and either take longer or shorter to get to the end. It's impossible to know what path the pawns did take. The total number of squares is either 21, 26, or 30 squares to reach the end, depending on the route the pawn takes. But possibly even longer if the game wants that, as the pawns move on their own.
Correction: 1. This is a question, not a plot hole. 2. You can't have a plot hole in a film based on what happens in another film made two decades later.
But to answer the question, while all was undone in the real world, that doesn't mean all was undone in the game world. Those are two different things.
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