It does not look like a campaign to me. On games and rounds board you need to give btc reward and it must be a raffle type reward where nothing is guaranteed. On service board you will also need to pay btc reward. It's free spins offering and I do not think it's going to make much difference if they offer it here or create a new topic for it in the gambling section.
But it really is. OP is asking for feedbacks about their casino by offering bonuses. It should be considered as a campaign. Some casinos have run their review campaign in games and rounds board by rewarding the users in BTC. You will also find giveaway or contest related thread in games and rounds board with free spins as reward. If I'm not wrong, then we will be able to get the free spin winnings in Bitcoin by choosing it as playing currency at Niyvi. Running this type of promotion in ANN thread directly conflicts with the second pinned post rules of gambling board.
To be specific, I'm referring to "Post in this thread for free x". That belongs in Games and Rounds. Though it isn't limited to that, in general you shouldn't be giving people incentives to post in your thread, it's disruptive to actual discussion.