i don't know who exactly you'd contact for server logs, depends if the match was broadcast as well.
*but*, the loser reports the match under the TWL guidlines, the winner doesn't need to do anything but bask in the glory.
the winner should only have to "claim" it's win if the loser is being a poor sport and not reporting the loss right after the match, or is perhaps disputing it.
in that case i'm sure the server logs will be in high demand, and would be easily found if needed.