Even if he cheats, he won't find anything here.

Another effective measure against cheating could be manual verification of completed game results: a moderator receives the save file before the final battle or surrender of one of the opponents, checks it, and if everything looks normal, the result is recorded. At least for new participants and during the initial period (~one week), this would be a good approach. Additionally, it would be beneficial to upload these save files to the cloud (also for about a week) so that anyone can check them if suspicions arise.
Otherwise, the HotA lobby will become a complete mess, and no decent player will want to participate. :(