I think your party should meet Shalelu a few days afar from Sandpoint, using her as hook and then start at Thistletop, probably finding Aldern Foxglove locked in a cell so they can save him, doesn't really matter these or those goblins. Let Nualia drop her journal (you can find one nicely done around) so the party can then go to Sandpoint knowing everything they need to finish the chapter once they clean the Catacombs of Wrath