The name of the establishment with the sign up for a dishwasher is the Seaside Inn. Thereafter it is referred to as the Malabar Cafe.
When Rosalie and Sadie have the confrontation in McGarrett's office, Jeb's shirt is almost completely unbuttoned in the front. When they are being led away to be booked seconds later, his shirt is totally buttoned up.
When the Fergussons are arrested at the end of the episode, not all of them are handcuffed. Jeb and Sam are clearly handcuffed, while Sadie, Monica, and Rosalie are not. The procedure would have been for all of them to be handcuffed, since the entire family was arrested.
When confronting the family in the final scene, McGarrett says the number of murders was over 150. But they killed an estimated 125 on the mainland, and only killed 6 after migrating to the islands.
The murderers leave copious amounts of fingerprints. But when Five-O team runs them through a national database, it comes up with no matches. The murderers have been doing their work (in the same haphazard style) in over 20 other states. After so many unsolved murders, it's impossible that their fingerprints would not be in the national database.