DNSCrypt-Proxy[1] already supports the randomized DNS resolver need[2]. It also supports DNS-over-HTTPS, providing assurance that even your ISP won't be able to snoop on all of your DNS queries.

While it doesn't support live comparison of DNS results, it can log out entries per DNS resolver and you can post-process those logs to validate their responses against each other, considering your queries will over time hit different resolvers. Not perfect since there are legitimate reasons to return different responses over time, but it's something.

[1] https://github.com/jedisct1/dnscrypt-proxy [2] https://github.com/jedisct1/dnscrypt-proxy/wiki/Load-Balanci...