He really needs to go away and get a top coach to remodel his serve completely. Many players have a weak second serve: James Ward, even Andy - both have good days and bad days.
But Josh not only has a low first serve percentage (today was 40%, which is somewhat low for him, probably due to the ATP match pressure), his first serve itself when it goes in is exceptionally weak compared to almost every other player he would typically come up against. Perhaps its too late, as he must be aware of this and may have tried many remedies, but what does he have to lose?