I would've enjoyed this event a lot even if I had lost. Even if I had lost and I thought that my entry was better than the winning ones, I still had fun looking at everyone's screenshots and making mine. Sure, if I lost I would've been disappointed. It's fine to believe in your own entry and think that it should've won. But the judge's decisions are out of your hands and you can't prove that they didn't have their reasons for their choices or that they weren't "careful." Even if you argue about who posted an idea first or what their subject/theme was, that doesn't prove anything definitive.
I participated in a screenshot contest event in Aion once. I LOVED my entry and I REALLY wanted to win. But I didn't, and I thought some of the winners had way worse shots than me. What did I do after I was disappointed by that outcome?