The losers will pay the winners. I don't think anyone will avoid a trade risk feedback if they do not honer the bets.
I do not see any difference in Symmetrick Ratimov's promise too. He can not deny a trade that was agreed between him and other parties.
There is definitely a difference. One is a donation and the second is a bet. As far as I can see, Ratimov is not a participant in this contest, so he certainly cannot receive any prize from it. There was no agreement between Ratimov and the participants here, except for a few thanks for his generosity.
So it is a donation, a bonus, there is no trade or bet on his part.
Maybe in his anger, he will try to deceive someone, but that is just biased speculation and not enough for a negative tag.
You can also look at it from the point of view that this sponsorship was an investment in his rating here on the forum. Now that that rating has been destroyed, it makes no sense for them to put money into it.