I learned that this adventure contains 23 pages and was published in 1992 by
Sage Lore Productions. The author wrote at least two other adventures,
P1: Sweet Wall of Death, and
P2: Gladestrom, both produced by
Underworld Publishing in 1992. Neither of these received great reviews.
Behind the Rose originally sold for $6.95. My guess is that it's worth $20 or less.
Truth is worth finding and life is too short to work for money.