I think you can identify the folk elements of any story by thinking about what makes a folk tale different or special from another kind of story. A quote that I love is:
"A folktale is a poetic text that carries some of its cultural contexts within it; it is also a travelling metaphor that finds a new meaning with every telling"-- A.L. Ramanujan, Folktales from India (1991)
Let's break that down and discuss how it related to Compromise by Vijaydan Detha, and how you can discover the folk elements by using that quote as a guide.
a poetic text
How is "Compromise" poetic? Can you find examples in the language that are like poetry? Especially in the descriptions of people, the landscape, music, or other cultural elements?
What are the cultural contexts? How can you be sure that this story is Rajasthani and not from some other place? Any specific mentions of Rajasthan or its culture help define the context are folk elements.
How is the story universal? There's a reason why this story was translated into English, and why it was written down by Detha. That reason is that it is a metaphor that can be related to any audience. Originally, folk tales had to appeal to different members of a similar community, but over time they get changed, translated, and travel far and wide because they are metaphors for universal life experiences. What, in "Compromise" is universal? Ironically, it is the universal elements that help you figure out the folk elements of a very specific cultural story. It's important to remember that as Nishat Zaidi wrote in his essay Traversing the Two Worlds: The Folktales of Vijaydan Detha, that Detha changes the stories to suit more modern audiences,
Without compromising their archetypal motifs, psychic underpinnings, and context-sensitive performativity, Detha metamorphoses them into captivating stories, which have a spellbinding impact on the minds of the modern readers.
In some ways, the act of modernizing and changing for the audience is part of the folk tradition, but be careful when noting the folk elements that you don't include the specific changes that Detha has made for modern audiences.