All NPCs are now able to see the Twins' Shop. Unfortunately for them, whenever they try the door, it is locked. They may, if they are lucky, catch a fleeting image of the twins in the window, but they are not being allowed in. Regardless of what they try to use - magic, technology, or explosions - they will not be able to get into the shop.

The door will open only when player characters are alone (or alone with other player characters). Otherwise you can keep knock-knock-knocking on Heaven's door (or Hell's?) but Bob Dylan has rejected you. He doesn't want to let NPCs in.

Because if he did, someone could arrest them. And that would suck.