Luffy did not use internal destruction aganst seraphim either. Don't know why you think he was using FS?
Only panel is Aramaki stabbing King. No panel of King resisting his plant otherwise Aramaki wpuld have commented on it.
Ace melted Kuzan ice so what nakes you think being top tier makes df immune to weakness?
If king cannot burtn aramaki plabt he cannot burn mochi. Mochi is also shown to be immune to fire several times.
How do you know luffy is not using internal destruction against seraphim?
Again i'll clarify it for you, aramaki never drained king he just restrained him. The difference was highlighted clearly when we saw queen's body shrivelled up while king's was not.
"Ace melted kuzans ice" What damage did it do? Absolutely nothing. Just because ace was able to counter the ice for one clash doesn't mean he would be able to do damage. So i dont know what point you want prove when we already know admirals are leagues above commanders.
Also why are you comparing greenbulls ability to aramaki.
They are vastly different. Greenbull also has a fire proof ability. Katakuri has nothing to say he would be able to resist magma like flames.