Unfortunately your seeding event is missing one critical component: You didn't explain how you "interpret" a game hash. You should publish a function and game rules before the seed is picked. That way we know you can't tailor your interpret (i.e. hashToGameResult) function based on the future results
Maybe he hides a malicious line of code therefore he cannot provide it publicly. The idea of onchain gambling such as he explained can attract some new gamers with the words and terms they aren't familiar with. But they should be cautious that such idea had already been used by others whilst having a script that just rigs the game and just simply gets your money.
OP, you are not advertising enough in this community. You can boost your audience by posting a proper announcement thread for that purpose, if you really want to attract some attention. It's your only chance of getting noticed. Also, the increased exposure will raise your audience's interest. The more you reveal, the more chance you have of convincing your audience to visit your site, or even become a customer. Look around and check out some threads from other casinos if you're not sure how it's done. That'll give you an idea of what you need to do. Another option is to hire someone to design and post a proper ANN for you.
Also consider interacting more with the community and posting useful information, answering questions, etc. that some people above already suggested. The more you do, the better. There's a good deal of competition in that market, so you'll have to do a few things right to differentiate yourself and get more attention.
I don't think the game isn't even serious enough. There are tons of the same game like this that are way more entertaining and trusted. Better play on reputable than risk having your funds stolen.