Perhaps the destruction of the Trident of Poseidon, which seemingly ended all curses, had the side effect of bringing back to life a man who had died via a curse.
The most obvious place is to go is where the last movie’s post-credits sequence teased.
Though, if the curse is actually broken, perhaps Bill Nighy doesn’t have to get covered in CGI and prosthetics.
In that scene, we saw a newly free Will Turner have a nightmare that Davy Jones had returned.