HIPAA Compliance

I couldn't find anything in there help, but I would try to contact them also at sales@nextdns.io and see if anyone there might also know if they have a BAA agreement, audits, etc. They do have a business and education tier plan and seems likely they would also have legalities accounted for.

I have  a hard time imagining that NextDNS is any less compliant than a default DNS provider. I would also be surprised if DNS was mentioned in HIPAA at all given what data it needs to do its job vs what HIPAA protects.