It's true that fixed matches exist, but we also need to analyze which leagues and teams they're likely to exist in. In the case of the Liverpool match, I think it's very unlikely that any Liverpool or Crystal Palace player would agree to participate in fixed-match schemes. This is because they earn a lot of money in salaries. To be bought, they would demand a very high amount, and it wouldn't make sense for someone to pay that amount because bookmakers have maximum bet limits.

For example, if the odds for a draw were @3.00 and the bookmakers offer a maximum bet of $5 million, the guy who wants to win by cheating contacts Liverpool players to deliberately arrange a draw. The Liverpool players will probably ask for $100 million. So, it doesn't make sense to pay $100 million when, at most, they would only profit $10 million if they bet $5 million on a draw.