I am a Chaotic Rogue and made a successful attempt to reach the Stronghold of the Master Assassin in the quest. However, I got into the wrong part of that level and have no way to go back.

I have:

• no polymorphic ring/wand
• a whistle and no other musical instruments
• no level teleport item (including cursed gain level)
• no ring of aggravate monster

Do I have to s and wait for a shrieker to aggravate the boss or starve to death? How can I get back to the above level?