I think I get what you mean. Cause in DMC Will wants to stab the heart to free his father, but Jack won't let him, cause then there's nobody to control the terrible beastie.
Will would be captain, but I don't think the kraken would obey him. I think it was Jones' pet sorta.. And Jack had the black spot, so it would come after him if Jones didn't stop it. And he couldn't if he was dead. I don't think it obeys the captain of the Dutchman, only Davy Jones himself.
And about the gooey stuff the kraken spit all over jack, I don't have the recipe, sorry 😛 They talk about it on the special features, but I don't remember if they say anything about what it's made of..
i'm pretty sure that the kraken spits all over jack. for one thing, it's all clear and goopy, for another, jack's hat comes out with it, and for a third reason, it looks exactly like fluffy's drool from harry potter and the sorcerer's stone. 🙂
also, i'm pretty sure that the kraken is davy jones' 'pet-like' creature. maybe only because davy jones has been the captain of the dutch for so long that he was the only one who had the time to 'tame' the kraken, or at least get it to obey him every once in a while. that's why i think it was very clever for t and t to get rid of the kraken in awe by having beckett make jones kill it. that's like, the ultimate show of power, if you can MAKE someone immortal kill basically their entire attack on other ships.