Is there? The casino is on a cheap $250 a month plan they don't belong on and they broke ToS with the domains. While also costing Cloudflare money each month (as the casino admits themselves, their traffic alone is worth up to $2000 a month).
It's absolutely in the right of Cloudflare to drop a customer that's bothersome. Casinos usually are (regulations, going around country restrictions), them costing them money on top is a massive issue.
120k a year is a big slap of course, but it's probably the amount Cloudflare would want to keep them on as a customer. If they leave, so be it.
I've seen it several times before at companies I worked at. They cheaped out and went with a tiny service plan to coast by. Or even broke ToS because it would be cheaper. That usually got stopped by plans getting dropped (GitLab Bronze for example), cheap plans getting limited, or the sales team sending a 'friendly' message that we're abusing their plan and how we're going to fix it. If you don't play along at that point you're going to get the hammer dropped on you.
It also wasn't 24h as the title says, the first communication happened in April. At that point they should have started to scramble, either upgrading to a bigger tier immediately or switching providers. And it's totally normal to go to the sales team when you break the ToS of your plan or you abuse a smaller plan. They're going to discuss terms, it's not a technical issue.
Edit: And I should also say, the whole "paying for a whole year is extortion" is bullshit too. Their CFO or CEO told Cloudflare they are looking at switching providers (as they looked at Fastly). So of fucking course Cloudflare is going to demand a full year upfront. Otherwise the casino could pay for a single month and during that month they switch away to another provider. So Cloudflare would still be thousands in the red with that ex-customer after they used so much traffic the last few years.