I know it is well after the close of the games, but I had to commnet.
I almost stopped reading this, as I don't tend to read stories that are so far out of the Potter reality. I'm glad I kept going.
This story is unique and refreshing, and really really good.
I strongly recommend that you file off the serial numbers, write a bit more to entrench the characters without the Potterverse assumptions, and publish it. The only thing you had in common with Rowling's work were the names, and a bit of the personalities. You created something new, and deserve your own readership.