After you overhear Ollie throwing Lupe out, use the bathroom. Nancy will sing a little jingle - "Call 1-555-Mystico, and prepare to be amazed." Do exactly that, and select "Something very special" when the prompt is available.
Then, head over to the fishing shack (which, as you'll see, is pretty functional still ), and start fishing! What you're looking for is a pink egg.
When you get the egg, you can now enter the Chinook room. Plus, the next time you go to bed, you'll have a very strange dream... this is what someone posted on her forum.