I'm not saying Sanji is guaranteed to awaken CoC. We don't even know if Gaban has it
		
		
	 
 Its more or less confirmed only , 
He uses Axe , so Haki is the only way out to be standing with Roger and ray. 
	
		
	
	
		
			All I'm saying is you're clearly denying that haki is a big part of Sanji's growth as a fighter as well
		
		
	 
 Yes I'm.  
But think yourself. 
Luffy and Zoro were both trained by Mihawk and Rayleigh , Specifically in Haki only. 
Whereas Sanji never has a Dedicated teacher for CoA , Yet he tapped into it. Very good tbh. 
But his Haki never Grew since then. We barely got CoA Feat from Sanji since then. 
Exoskeleton was more or less a CoA alternative Upgrade. 
What I'm saying is , Oda is taking different route with Sanji unlike the usual AdCoC path which Luffy and Zoro were Limited to.