Silas Tor and His Wondrous Trinkets

This event should play out as described in the original adventure. Using the Arcana skill to sense the presence of magic (DC 25) reveals the dwarf's trinkets as frauds, and Insight checks (DC 27) uncover the deception as well. You can allow the PCs to try and calm the crowd down and disperse them before driving Silas away, but as long as the dwarf leaves before causing too much trouble the PCs earn a victory point.