Are you asking about why Moz would or would not consider them duplicate, or why Google would or would not consider them duplicate?
We don't have knowledge of exactly what factors Google uses to detect duplicate content. We approximate the best we can, and give a notice when we see things that look substantially alike.
I did get the two pages in the original question to load. There are only a couple of words that are different, and the rest of the content is identical, including the related events. As a side note, I don't know that people looking for MLB tickets would consider "The Mu Gamma Gamma Chapter Seersucker and Sundress Summer Affair" to be a related event.