Interesting concept, and the setup revealed in the diary entries was fascinating. I love the way the prisoners strategized their way out, and it was a really promising start.
However, I do have several nitpicks, but take with a pinch of salt.
1)The beginning: Leon reading the diary sounds very artificial, honestly. I'd suggest jumping directly to diary format immediately. You've sprinkled enough clues that a reader familiar with Gundam Wing can tell who it is (China, Meiran = Wufei) and really the diary entries are the juicy bits. Prologues can have a different structure from the actual story, since they're setting up the scene.
2) Sometimes, spell check isn't enough. Meiran is the common spelling; unless you have an original character called Merian?
Spellcheckers don't pick up on punctation either. Shower some affection on your commas, they're needed.
Thank you for sharing!