Perhaps - of the few people that get to level 15, most would probably be completing optional rooms anyway, especially DROD players. Besides, it happened, so can't be that improbable
Later today I'll restore back to the point where I had a black door, recomplete the optional room, and tell you exactly where I got the exit room message. I have a feeling it won't be after completing that room, but visiting some room later on. (The only rooms I hadn't visited were the ones along the path to the secret).
I had wondered perhaps if there was a room available from rooms near the entrance that I hadn't visited but could have (since you can't backtrack through 1E), but that doesn't seem to be the case. Will let you know.
[Last edited by TripleM at 11-24-2010 01:04 AM]