SCHOLAR! You are wrong, wrong, wrong again! - although I can understand why you were mistaken, there is one place in Josephus where it says that Nebuhcadnessar, while he was still crown prince, initiated the siege on Jerusalem on the orders of his father, and then destroyed it. However, in that particular passage, the nature of that siege, or how long it lasted, is not mentioned! You should then read "Antiquities of the Jews, book X, chapter 8", in which we read Josephus full description of the destruction of Jerusalem and the Temple:
"5. And now it was that the king of Babylon sent Nebuzaradan, the general of his army, to Jerusalem, to pillage the temple, who had it also in command to burn it and the royal palace, and to lay the city even with the ground, and to transplant the people into Babylon. Accordingly, he came to Jerusalem in the eleventh year of king Zedekiah, and pillaged the temple, and carried out the vessels of God, both gold and silver, and particularly that large laver which Solomon dedicated, as also the pillars of brass, and their chapiters, with the golden tables and the candlesticks; and when he had carried these off, he set fire to the temple in the fifth month, the first day of the month, in the eleventh year of the reign of Zedekiah, and in the eighteenth year of Nebuchadnezzar: he also burnt the palace, and overthrew the city".
Perhaps you should do your homework before you come on claiming that Josephus supports the WTS`s claim!