Last year a <sudoku gremlin> was being a minor nuisance by erasing all the single digits in my candidate grids ,

but now it's worse -- The gremlin is erasing all the single digits and also all the naked pairs (if there are any)!

Here's the latest vandalised grid:

- Code: Select all
`347 | 3456 46 | 3567 37`

3478 468 | 1346 1346 | 3678 378

268 38 268 | 3569 3569 | 568

---------------------+----------------------+------------------

1678 | 14678 468 |

678 | 3678 367 | 38

18 68 | 13689 689 1369 |

---------------------+----------------------+------------------

248 | 45789 4579 | 58 5789 278

128 189 | 5689 569 | 158 589

18 1489 | 489 479 | 789

Can anyone recover the whole grid and solve the original puzzle [without guessing where any missing candidates are located, and without using brute- force T&E]?

[Edited to make the puzzle more interesting, and to make the intended humor a bit clearer.]