Cloudflare strips the edns info from requests. Edns contains the IP address of the client making the request. Cloudflare strips it for privacy reasons. archive.today has an issue with this and therefore refuses to answer dns requests from Cloudflare. According to archive.today this is because not having the requesting IP address prevents them from complying with per country requirements. But archive.today will happily reply to dns requests from other resolvers which don't include the edns info. You can test this yourself using dig with the +noedns flag.