If I registered my domain name with someone else, is there any way a person can see that my subdomains were registered here? I’m assuming that all of the redirection is done locally and that I therefore am not breaking the privacy offered by my proxy registration by registering subdomains, but I wanted to double-check.
Registration and hosting are two different things.
But someone who is determined can pretty easily find out where you’re hosting your site, be it a domain or a subdomain.
If the WHOIS for your domain is anononymized via proxy, nobody is going to find out who you are unless you yourself provide that information on your website(s).
Subdomains don’t have any directly queriable WHOIS info anywhere, if that’s what you’re asking.