While the list of names is true for who your allies will be, what might be helpful is having the list of 7 side quests and 2 errands that need to be completed to have all allies for the final battle. See below:
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Side Quests and Errands:
Traitor’s Bounty
Queen’s Gambit
A Moments Peace
A Daughter’s Vengeance
Sun and Shadow
Honor The Fallen
Sunstone Rock
Hunting For the Lodge (Errand)
Hunter’s Blind
Deadliest Game (Errand)
Redmaw
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You can check if you have completed these in your quest log. Please note that all other side quests and errands do not matter for this achievement. Only the 9 listed above.