No one can promise to put gambling sites in the top ten.
You can get in the top ten if you sell macadamia nuts or toilet scrubbers or something with little competition, but people who have the skills to put a gambling site on top are either doing it for themselves (because the income would be so much better than they would ever make doing it for the public) or they are working for casinos or top gambling sites privately.
In our industry, these type services do not work.