I'd run damn fast away from that site. Never heard of them, half their website is broken, all of it looks out of date. There are plenty of other domain registrars to pick from - you don't have to use them.
I believe PublicDomainRegistry is owned by ResellerClub. If you were to create a reseller account with them, and then register a domain through it - It would show up as PublicDomainRegistry.com in the whois.
Yes, that is correct. Public Domain Registry is the Registrar on record for ResellerClub. You can sign up with them and buy domains from them using this link - http://www.resellerclub.com/signup-now