I like your comparison to the lost city of Atlantis. That’s powerful imagery and very accurate. The third paragraph was wonderful & inspirational! Motivated word choices.
I hadn’t heard the “preferably both murder and betrayal at the same time” version before, so that made me laugh.
The suggestion about letting your characters loose is a great one! (And amusingly phrased.) Overall, very good suggestions for livening up a dying novel.
I marked a few commas & things on behalf of Airianna; normally this is her territory, but she’s busy so she gave me her blessing to do an editing run. I was working on the edits “offline,” so I put my comments in brackets within the text, since other formatting wouldn’t copy & paste. If the note has “IMO” in front of it, that means it’s just my personal suggestion for flow – not a grammatical “rule.”
BTW, I’m rooting for you, Varon! Go catch up! (And maybe post a sample of your novel for us to read?

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If I am to be [IMO: “If I were”] 100% honest, I'm not quite sure what to write. As of this moment, it is 12:17 am on November 17. My word count is 9,297, [semicolon] that's 19,042 words behind. As you can see, I'm still suffering from Week Two blues [IMO: capitalize “Blues”], as Chris Baty calls them I believe. [IMO: drop “I believe.” The flow kinda catches here.]
Perhaps you're also suffering from an extended case of the Blues. Don't fret [comma] chum, [semicolon] everyone gets over the blues [capitalize “Blues,” OR don’t capitalize it in the previous sentence] eventually. No illness is permanent. They just sometimes need a lot of time to get over.
You may also be cheered to know that the saying "It's always darkest before Dawn" [IMO: don’t capitalize “dawn”] also applies here. We're sunk in the deepest trench of the darkest ocean, and it's here that Atlantis can be found. In Atlantis you find [IMO: “will find”] treasures beyond compare, light, relief, and a boost to the surface. You will soon find your second wind to fill your sails and propel you along the smooth seas of Thanksgiving break, if you have one.
On a more practical note, how's the plot? If by any chance your characters are searching for Atlantis, this probably the spot where they should be in the deepest trench of the darkest ocean, [no comma] and about to find it [IMO: replace “it” with a phrase like “the lost city”]. If not [IMO: replace “if not” with something clearer like “If they’re not searching for a mysterious city”], thing [think] figuratively.
To compare my plot with the search for Atlantis theme I've got here, my characters are about to fully embark on the quest. They've started but not yet fully committed. [IMO: I’d add a sentence here explaining what you plan to have your characters do next, as a parallel to finding Atlantis]
Another well used [well-used] saying, especially on the NaNo forums, [IMO: add the word “is” here] "There's nothing like murder or betrayal to make a story more interesting." Chances are, [no comma] you've already heard that, and maybe even its second form. [IMO: colon and make this all one sentence] "There's nothing like murder or betrayal to make a story more interesting, preferably both murder and betrayal at the same time."
You may not be sure how this fits into your novel, but it can. Do you have a character that appears to be jealous or unhappy? You already have someone with a reason to betray the character's [IMO: replace “character’s” with “the main character’s” for clarity] allies. A simple betrayal can cause external and internal conflict. It's often the internal that hurts the most.
Perhaps you don't like your characters anymore. They're angry and don't listen to you. They aren't heroes anymore, [semicolon] they decided to become antiheros. What do you do? Let them loose and see how they like the consequences. Death, destruction, and overall chaos ensue when they failed [fail] to do what they tell you [you told them?]. It should get them back on track, or at least teach them a lesson. They go exploring sunken ships, where some unimportant non-hero character gets eaten by a shark or some other grisly fate.
In revamping all these, you mustn’t forget to take care of the setting. The setting is perhaps the most under rated [underrated] aspect of writing. There are entire books about making plot and character, but not so many about setting. Do not under estimate [underestimate] it. Not only does [do] lots of description boost your word count, it [but it also] creates a foundation for your readers. I know that when I read “The Lightning Thief,” [if this is a novel, italicize the title] the lack of description and un-named characters made me dis-like [dislike] it. Everything else was alright [two words – “all right” <grin>], but the lack of description made it seem to be [IMO: add the word “written” here] in a vacuum.
Or maybe you no longer care about your story as a whole. This is harder to deal with. You mist [must] revitalize the spark within you. Add murder and betrayal. Send one of your favorite characters deep into danger, with no hope of escape. Add a character you like. Make the story interesting again, [semicolon] add something you really want to try, but don’t think it will fit. Whatever you do, make it interesting. If you don’t [comma] the readers will sense your boredom and feel the same.