I say in the third movie he will either:
1) Cutt his way out of the Kraken like he did to the coffin in the second movie,
or
2) The Kraken will digest him and he will fly out of the water lol
Or
3) dalma will bring him back
or
4) davy jones will bring him back as a slave on his ship and they will rescue him or IE he will escape on his own somehow
My other theory really died when you guys explained it, so this leaves me really confused at why they ended this movie the way they did.