After you can examine the body of Edgar Cuddles won't leave the club until he finds all the clues.
You have to find or click these items
Open Edgar's jacket and check the pocket.
Open Edgar's left hand.
Next to Edgar's body.
Next to the stain. Left and up from Edgar's body.
Tinkle's "grandmother" mentioned about a wall where wind blows.
A wall, where there comes air out?
There is an air vent next to the elevator. Use the air vent.
Take the paper from the vent. You can now exit the club.