YABI. Why even ask for the second match? Was your initial study incomplete, or, perhaps, flawed? If so, why did you not include that detail in this post? If not, your rendezvous with this old classmate seems like nothing more than an exercise in redundancy at best. I posit that you have fallen victim to the emotion humans refer to as pride. One of their most basic negative emotions, if I correctly recall my ancient human history course.
It is my recommendation that you take a leave of absence from Starfleet. You have clearly spent too much time among humans. A decade or so of meditation in a monastery should help you to reclaim your logic.
NBI. A captain of mine once said that it is possible to commit no mistakes and yet still lose. Perhaps your opponent was celebrating having made no mistakes?
Assuming an alternative goal is indeed the logical response here. It is plausible that the opposing team recognised that they could not triumph against a Vulcan team and set themselves a more achievable goal, for example scoring within 80%.
EIH
While the human’s behavior following the loss of the game is illogical, as humans are want to do, your dismissal of their responses to your clarifying statement regarding their loss as ‘petty’ is inherently illogical as well. Doing so instead of, as logic would dictate, rigorously testing their response for potential validity, if only in a human context, has resulted in your hypothesis being unanswerable with available information. Please keep in mind that while the actions of humans often appear illogical, this commonly is due to a lack of context surrounding those actions or understanding that, being highly emotive beings, the logic of their actions may be derived from a not immediately accessible source given a Vulcan perspective in observing the events. Further inquiry in this matter is generally welcomed by persons engaging in apparently illogical behavior, and your failing to clarify these conditions at the time of the event necessitated the query passing to this board, which could have been a post in /c/humansubspacemicroblog providing insight into this phenomenon instead of us attempting to ascertain fact with incomplete data.