Sub Crocodile has class. He throws out two insults in that whole exchange. One as a tongue-in-cheek display to the townspeople to keep up the facade of the 'big bad pirate' who's actually a hero. (which also, was a facade). And the second as a final parting blow after displaying his clear superiority to the other pirate.
Dub Crocodile, on the other hand, has all the elegance of a 6th grader at recess.
Bully: "You're a stinky head!"
Dub Croc: "I'm a stinky head, huh? I don't think so. Idiot bully."
…...So that's what you deduced he sounded like after hearing FUNi's dialog. Really? 'Cause I can tell you right now that that's not AT ALL what I thought when I heard the dialog, and I can testify for most of the others who have seen that scene as well.
I can give you that he sounds more "raspy" than sub Crocodile. But the dialog is fine. Certainly not at "sixth grader" level, but if you've seen any 6th graders talk like that, enlighten me. 'Cause I would like to listen to that tale.
And I mean compared to the real dialog, not your phony one.