In the end, looks like Judge's DNA modifications just had a late delay, with Sanji gradually awakening his powers while growing, with the first hint of that happening in Enies Lobby when he unlocked his diable jambe technique.
We used to think it was friction, but I guess Oda wanted to create a connection with the germa modifications he explained in WCI
We used to think it was friction, but I guess Oda wanted to create a connection with the germa modifications he explained in WCI