One Piece: The reason Zoro isn't the Vice-Captain explained - Dexerto

One Piece: Every major villain who appeared in live-action ranked - Dexerto

General & Others - Officially confirmed: Zoro is the vice captain, Page 13

One Piece anime: 10 best upcoming fights in Egghead arc - Dexerto

Oda officially confirms that Zoro is - ONE PIECE Fanpage

General & Others - Officially confirmed: Zoro is the vice captain, Page 14

General & Others - Officially confirmed: Zoro is the vice captain, Page 13

Oda officially confirms that Zoro is the 2nd Strongest but he is not the Vice Captain of the Crew! - One Piece

General & Others - Is Zoro the vice-captain or close? Is he Lufy's right-hand man?, Page 13

Oda clearly stating that Zoro holds no position as first mate or vice- captain in the crew but some fans want to run with their own assumption and take it as fact above