Just to clarify - Cloudflare have POPs behind the great firewall of china in cooperation with Baidu. That is not to say Cloudflare routed sites are all accessible through CF, but it's certainly not a blanket statement either way.
Yes but you need a "license" given by Chinese Gov. Otherwise your website will still be routed to edges outside of China.
And the bigger problem is the CloudFlare DNS, it is not working well in China.
Not sure if this would work better.