Excellent critique, Apognophos! It's going to be useful for when this comes up in discussion with the JWs I know.
A couple of quibbles:
2. Upon becoming king, Hezekiah rebels against Assyria (2 Kings 18:7). Being that they are a vassal state left to rule themselves, the only conceivable way to rebel is to stop paying tribute.
3. It is at this point that the Assyrians attack (2 Kings 18:13)... because they were provoked by Hezekiah.
As you say, Hezekiah's rebellion has been placed early in his reign. It's followed by the account of Assyria's attack on Samaria in Hezekiah's 4th year. However, it's only in Hezekiah's 14th year that Assyria attacks Judah. Either it wasn't a serious rebellion up to that point or the Assyrians weren't too bothered (unlikely) or Hezekiah only plucked up the courage to rebel later in his reign. What is clear: something ticked off the Assyrians in that 14th year, i.e. Judah switching allegiance (2 Ki. 18:19f.).
5. Hezekiah then begs for forgiveness from Assyria, and is fined a certain amount of gold and silver. To make the payment, he gives all of the silver in the temple to Sennacherib, as well as lots of gold. Where does he get the gold? By stripping it off the posts at the entrance to the temple! (2 Kings 18:14-16)
[Later comment] Next, he pays Sennacherib to leave him alone by pillaging God's house of everything shiny, while apparently leaving his own treasure-house alone.
He took silver from his own treasure house too.
(2 Kings 18:15, 16) Therefore Hez·e·ki′ah gave all the silver that was to be found at the house of Jehovah and in the treasures of the king’s house. At that time Hez·e·ki′ah cut off the doors of the temple of Jehovah and the doorposts that Hez·e·ki′ah the king of Judah had overlaid and then gave them to the king of As·syr′i·a.