The impression I arrive at is that the rooms are supposed to be viewed individually, out of context, not how they are related to each other on the board. In other words, not to be seen as connected to each other; just all represented on the game board.
Obviously the living room was not
in the center of the house, and there was a hallway leading to all the bedrooms. Not so on this game board.
Perhaps it has something to do with needing to move game pieces "around the board" as you play. The actual layout of Blanches house would not lend itself to doing that very well.
Why the details of each room isn't more accurate I can't account for.