How to Trap Your Moderator

Question

You have locked your least favorite moderator behind a 27x27 Sudoku...
Now you regret, but you have forgotten how to solve the puzzle...

CSV version:
 ,  , 1,  ,  ,  ,  ,  ,  , 5,  ,  ,  ,  ,  ,  ,  ,  ,  , 7,  ,  ,  ,  , 6, 1,  
6,  ,  ,  , 5,  ,  ,  ,  , 2,  , 8, 9,  ,  ,  ,  , 2,  , 4,  , 9,  ,  , 7,  , 9
2,  , 9,  , 7, 6, 3,  ,  , 4,  ,  ,  , 3,  , 4,  ,  ,  ,  , 5,  ,  ,  , 4,  , 8
 ,  , 8,  ,  ,  ,  ,  ,  ,  ,  ,  ,  , 4,  , 6,  ,  ,  , 6,  ,  ,  , 7,  , 4, 5
 ,  , 4,  , 7,  ,  , 6, 1,  ,  , 5,  , 6,  , 8, 9,  , 2,  ,  , 8,  ,  ,  ,  , 2
 ,  ,  ,  , 1, 2, 4, 3,  ,  , 6, 1,  ,  ,  ,  ,  ,  ,  ,  ,  , 1,  , 4, 6,  ,  
 , 8,  ,  , 2,  , 5,  , 8,  , 5, 3,  ,  ,  ,  ,  ,  ,  ,  ,  ,  ,  ,  ,  ,  ,  
 ,  ,  ,  ,  ,  ,  ,  ,  ,  , 1, 4,  , 7,  ,  ,  ,  , 4,  ,  ,  , 6,  , 3,  ,  
 , 5,  ,  ,  ,  ,  , 4,  ,  ,  ,  ,  , 8,  , 1,  , 5, 3,  ,  ,  , 7,  ,  ,  , 2
 , 7, 5, 8, 3, 9,  , 4,  ,  ,  , 9,  , 4,  ,  , 7,  , 1,  ,  ,  ,  , 6,  , 8,  
 ,  ,  ,  , 6, 4,  ,  , 6,  ,  ,  ,  ,  , 8,  ,  ,  ,  , 4,  , 5,  ,  ,  ,  , 2
 ,  ,  ,  ,  ,  ,  ,  ,  ,  ,  , 5,  ,  , 2, 6,  , 8,  ,  , 7,  ,  , 3,  , 4,  
 ,  ,  , 1,  ,  ,  ,  , 4,  , 8,  , 1,  ,  ,  , 9, 5, 8,  ,  ,  ,  ,  , 4,  ,  
3,  , 5,  , 8,  ,  , 1, 2, 2,  ,  ,  ,  ,  , 1,  , 3,  ,  , 9,  , 6,  ,  , 8,  
 ,  ,  ,  ,  ,  ,  ,  ,  ,  ,  ,  ,  ,  ,  ,  ,  ,  , 4,  ,  , 5,  ,  ,  , 3, 2
9, 1, 6,  , 6,  ,  ,  ,  ,  , 7,  , 8, 9,  ,  ,  ,  ,  ,  , 9,  , 3,  ,  ,  , 9
4,  ,  ,  , 9,  ,  , 7,  ,  ,  ,  ,  , 6,  , 5, 2,  ,  , 5,  ,  ,  ,  ,  ,  ,  
 ,  ,  ,  , 2,  ,  , 9,  , 4,  ,  ,  , 1,  ,  ,  ,  , 7,  ,  , 9,  ,  ,  , 1,  
 ,  ,  , 6,  , 9, 6,  ,  ,  ,  ,  ,  , 7,  ,  ,  ,  ,  , 3, 1,  ,  , 7, 5,  ,  
 ,  ,  ,  ,  ,  ,  , 9, 4, 4, 1,  ,  ,  ,  , 9,  ,  ,  , 2,  ,  , 6,  ,  ,  ,  
 ,  , 3,  ,  , 1,  , 5, 8,  ,  , 3,  ,  , 8,  ,  ,  ,  ,  ,  ,  ,  ,  ,  ,  ,  
 ,  , 2,  ,  , 7,  ,  ,  ,  ,  ,  ,  ,  ,  , 4,  ,  , 2, 4,  , 4,  ,  , 9, 4,  
 , 8,  ,  ,  ,  ,  ,  , 2,  ,  ,  , 3,  ,  ,  ,  ,  , 3, 7,  ,  ,  , 3,  ,  ,  
 ,  , 6,  ,  ,  ,  , 8, 7, 5,  ,  , 8,  , 7,  , 1,  ,  ,  ,  , 6,  , 8,  ,  , 7
 , 1,  ,  ,  ,  ,  , 2,  ,  ,  , 2,  , 3,  , 5, 2,  , 8, 6,  , 3, 2,  ,  ,  ,  
 , 7, 5,  ,  ,  ,  , 6, 1, 5, 7,  ,  , 8,  ,  ,  ,  , 1,  ,  , 5,  ,  ,  ,  ,  
 ,  , 6,  , 7,  , 3,  , 8,  , 4, 9,  ,  , 6,  ,  ,  ,  , 9, 4,  , 4,  ,  ,  ,

Jens · Accepted Answer

As others have seen, the 9 sudokus are generally unsolvable because they have numbers which repeat in rows and/or columns. However, there is one exception, which is the central sudoku. It turns out it is solvable and with a unique solution:

There is something striking about the solution, namely that the central 3x3 square has a very nice ordering of its numbers. Suppose the central sudoku is a mapping of the total sudoku such that each 3x3 square in the central sudoku shows how each 9x9 sudoku has had its 3x3 squares moved around. For example, in the top left 3x3 square of the central sudoku, the number 1 is in the middle of the left column. Suppose this means that the top left 9x9 sudoku has had its "number 1" 3x3 square moved to the middle of its left column, when it should in fact have been at the top left (in the order given by the central suduko's central square). If we rearrange the position of each 3x3 square of each 9x9 suduko so it matches the ordering of the central sudoku's central square, we get this:

And if we then check each 9x9 sudoku, we see that there are no longer any repeats of numbers in rows or columns. In fact, each of the sudokus are now solvable and with unique solutions:

How to Trap Your Moderator

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