From the wiki..
Winning without Anora: Complete Lost Templar and Tortured Noble successfully before the Landsmeet and either free Vaughan or complete The Trial of Crows. Use the "focus on the Blight" argument in the first round, the "torture dungeons of Howe" argument in the second, and the "poisoning of Arl Eamon" argument in the third. This will ensure the Grand Cleric's denunciation of Loghain and the votes of Alfstanna, Sighard and Wulff. If done successfully, Logain will bring up the topic of Anora being held by the Wardens. To this, use "What? I did it to protect her from you!" and subsequently the option "What?!" when Anora reveals her betrayal.
Note: It seems that arguments which garner support but are not backed by quests (Blight and slavery) do not contribute to the point gain, therefore the additional votes of Vaughan and/or the mysterious nobleman are required.
The wiki has been wrong before. You do not need them, period. I didn't get that Crow noble's support since I didn't even do the quest and killed Vaughan in his cell earlier, and still won or lost based on the Anora responses. And the guy in my Reddit post confirms the same damn thing. To quote it-
"Let me break it down below:
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(Persuade) The Blight is the real problem, not Orlais!
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Tell that Loghain allowed Howe to torture prisoners.
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Tell that Loghain facilitated a blood mage's escape from the Chantry, and poisoned Arl Eamon.
At this point, you'll have achieved public verbal support and confirmation from the various Nobles, and then Loghain will sidetrack the debate and bring up your involvement in "kidnapping" Anora, and publicly question whether you've killed her or not. This is where the dialogue choices will win or lose the Landsmeet, even if you follow the same order of debate points listed above!
Lose
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[In response Loghain's accusations against you regarding his daughter] We're talking about YOUR crimes here.
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[Anora appears, reveals that she has turned against you] I knew you were working for Loghain.
This results in a slightly longer dialogue sequence from Loghain and Anora denouncing you, which seems to sway the unspoken opinions of the unnamed voters, as reflected by the unnamed final speaker (on ground level, red moustache) who names Loghain as the one to support. This character appears to simply be the indicator of "who won", regardless of verbal noble support. The mechanics of the Landsmeet are actually defined by an unspoken point-system of effective argument and retort in the eyes of those characters present - ie: Whether you argued with momentum and reason over bitterness and slander.
Win
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[In response Loghain's accusations against you regarding his daughter] What?! I did it to protect her from you!
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[Anora appears, reveals that she has turned against you] What?! [Alistair comments, "Oh look, she's turned against us. And we were hoping she'd turn out to be a nice despot."]
This results in a short dialogue sequence from Anora denouncing you, which seems to sway the unspoken opinions of the unnamed voters, as reflected by the aforementioned unnamed final speaker (on ground level, red moustache) who names the Warden as the one to support.
In short, once the optimal conversational order of proof is brought forth by the Warden who opposes Anora, there appears to be one or two final "points" earned in that short exchange regarding Anora. Perhaps your public surprise when Anora reveals she's turned on you sways sympathy in your favor, perhaps it shows the lies and immoral aptitude of Loghain and his daughter the Queen. Perhaps both. The bottom line is that there appears to be much, much more than meets the eye at the Landsmeet, and even the DA:O community's general understanding of the point system is still woefully underwhelming"
I can confirm the above is fact.