I have talked to my supervisor, who told me that I can include it in my essay so long as I do without any specificity. The only thing that I have used in my essay based on the real instance is the subject matter and the characteristics of the caller (things I admired, such as his optimism). I made the rest of it up. My entire essay is basically a "what if" scenario. I was struggling with the entire ethics scenario, but I think the way I have written my essay allows me to convey my passion while also protecting the confidentiality of my callers.