The Boys knock on Victor's door, he opens it and hangs up a 'Do Not Disturb' sign and closes the door. When the Boys return a little later the sign has disappeared.
Anna goes into Victor's room . After Laurel and Hardy knock on the door a 'Do Not Disturb' sign is put on the door which has disappeared when they return moments later.
The lyric of the final song says, "In Swiss that's 'good morning to you.'" There is no language called "Swiss." Swiss citizens speak German, French, Italian or Romansh.