The only thing that the winner of this fight depends on is whether or not Calzaghe turns out to have become shot himself. If not, he beats Jones anywhere in the ring he likes.
Jones needs to start aggressively. If he doesn't he won't get in the fight full stop.
Jones can still beat Joe though no doubt. Calzaghe is my favourite fighter but Jones even now could prove to be too good if he winds back the clock a little.
If he is truly a shell, he gets stopped by Calzaghe.