All DNS zones on CZDS have the same format, and AFAIK all nTLDs are required to use it. But you're right for ccTLDs -- everyone uses their own format and most don't even allow you to get the zone file. There are some companies that provide similar lists from crawling data though (e.g. https://zonefiles.io/). - Source: Hacker News / about 2 years ago

There are all kinds of ways Google could find out about your site. For many top-level domains, it's possible to just download a list of all domain registrations: https://zonefiles.io/. Source: over 2 years ago

Whoisology is a massive, searchable database that provides an in-depth view of domain name ownership through its cross-referenced domain name whois records. The tool's priority is on reverse whois, to assist with security, cyber crime investigation, research and other business endeavors. Our appreciation for this recommendation goes to crashdodson. Source: over 1 year ago

It looks like the domain was registered in 2006 (info from https://whoisrequest.com/history/), and went offline in 2018. A long shot, but if the person who registered the site didn't hide behind a privacy option, you might be able to dig up their email address from looking into the historical WHOIS data via a site like https://whoisology.com/, or https://www.domainiq.com/. Source: almost 2 years ago

More then just reverse lookups on emails, Whoisology https://whoisology.com/#advanced Website analytics, Traffic, location, Overview etc http://www.statscrop.com/www/inteltechniques.com Youtube Video meta Data Viewer, GPS, Keywords etc http://www.amnestyusa.org/citizenevidence/. - Source: dev.to / about 3 years ago