Hythlodaeus hadn't been to visit Emet-Selch at his new job yet. He knows he's working, but he wants to see him- and so he finds his way to the G-String and lets himself straight into the office without knocking.

"Not a soul in sight to greet me- truly convenient." He sits himself on the edge of the desk and grins at Emet-Selch. "Why, one can simply walk all the way to your office and barge right in!"

Especially if they know exactly where Emet-Selch is thanks to soul sight... there may as well have been neon lights telling Hythlodaeus where to go.