I would advise you not to rely on sports prediction sites because it's not one hundred percent accurate, they only have ideas on the outcome of the game but the best way to use their predictions is to compare it with the head to head statistics of the game that you are selecting, you can check out forebet.com, their predictions are free and 60 percent reliable, avoid websites that asks for subscription fee to get games cause most of them are scammers and they might hack your bank account if you input your card details on the site
Providing card and bank details on a random and untrustworthy site is definitely not a good idea, but even if a site or a platform is asking for cryptocurrency payments, it's still not good because as you said, such services are not completely reliable, and when something isn't so reliable, there is no point in paying them money to use their service. When you are into sports betting, you should be able to make better predictions than these websites.
If a random website on the internet is making better guesses and predictions than you, you aren't supposed to be into sports betting then, simply stop making bets and find something else to do, something that you know how it should be done and you shouldn't need any help or assistance to get it done.