I think the blue fire is super god ACoC,
I feel like Sanji won't get ACoC, even though he probably will surpass yamato.
Oda's weird about power ups. He doesn't give kaido and linlin confirmed awakenings, he doesn't give Kid and Law any advanced haki, he doesn't give the mid trio haki. I have the feeling that Oda cares more about giving characters unique power ups.
Rather than have Sanji awaken ACoC, I think its much more likely that Sanji will get more genetic power ups when he meets Judge/Vegapunk.