Here's a question: is the tournament intended to be open (for anyone who wants to participate) or closed (by invitation only)?
If it's closed, I can add a few names to the list in the first post.
Gynnar (a very strong player from St. Petersburg, a big fan of the game), Brennan (an excellent young player from the Moscow region), Navuchodonosor/Captain (one of the strongest Heroes II players from Ukraine). In addition, there are two very strong Heroes II players from St. Petersburg: DR28 and SDV. I haven't seen their reports on online games, but I know they play online, and according to Qwerty, they have been among the strongest players in the Russian-speaking internet for offline play in recent years.
Next, Kama is a strong and thoughtful player from Moscow; when he's "on his game," he can beat any opponent.
And of course, there's the living legend of Heroes II – GreatGenius (Moscow)!

In principle, there's also a whole constellation of very strong players from St. Petersburg, starting with Horn (the creator of TE), who have switched to Battle.net, but could certainly show their skills if they wanted to.

Of course, this list is by no means exhaustive; it just includes the players I know.