It's not really cheating. It's stupidity on his part as he would have to still bid with each account to stay in it. It doesn't make you bid any more tokens (still 1 per round) and he's now spending twice as much game money.

The only issue you would have is with the inflated cost of the player, but if he's worth that much to someone that they'd be willing to pay that, you can't really argue.

Cheating would be my opponent in round 1 of the cup who spontaneously hacked the game midway through the match while I watched and changed the score from 1-0 to 4-0 to demoralise my players...