[Carl Johnson]

Well obviously it's not possible to find such service as a lay man, although I know it exists. Fixing of matches is high level, highly classified stuff. You need to be on a certain level or certain position or hold certain office. Only reason anyone brings you in on it is probably to bribe you, to prevent you from whistleblowing on the whole setup, or perhaps just trying to help you. Nobody in this business needs your money lol.
Think of it this way, people behind the websites you mentioned can make millions, in fact billions, by just using the service they claim to offer. So why would anyone in such a position need your few btc and risk the fact that you may be a spy whereas he can just stay in his small tight circle and keep making millions every week? This is common sense mahn!
You have to always think as a fraudster, nobody doing this needs your money, no amount you pay the person that he cannot earn from betting on the regular fixed matches himself. So bringing you into the business is just him trying to ruin a beautiful set up and no legit person is ready to take that risk. If I'm in on something that huge, I would never sell such information even if Elon Musk offer me his 200 billion dollars! Use your senses mate