@jgrahamc how can you even answer that question when you didn't detect the issue yourselves?
The email we received was a joke, OK great our domains 'weren't affected' in the sense of memory dumps weren't being injected into our HTML, and luckily we only proxy static images/html through CF so at worst a visitor's google analytics cookie could have been leaked, but on a personal level any person who has used any CF-proxied website (e.g. Uber) in the past few months is potentially affected.
Whether or not you think it's likely anyone discovered this earlier, the fact remains that private data is still in various public and private caches around the world. It's a monumental cock-up that will require every CF proxy customer to rotate keys, invalidate tokens and force mass password resets to ensure complete peace of mind for millions of consumers who will probably never hear about this issue even though their credit card information, passwords and private messages could be floating around the internet as part of a cached version of a website they've never even visited.
Even the way you're looking for cached data to find affected customers - yeah ok, for page x.com/y you found data for customer z.com, but what about the other million times that affected x.com/y page was loaded, that could be data from a million different customers that someone else (human or otherwise) saw, whether they realised what it was or not. And trust me there are more than a few people on the planet who would know _exactly_ what they were seeing.
Forget about shareholder value for a minute, please, because it's an absolutely fatal mistake for your company to downplay an issue like this.