Manage multiple subdomain on a different nameserver?

Question

I have a domain, example.com which is managed on Cloudflare, and I would like to manage multiple sub-sub-domains, that end with .internal.example.com, such as one.one.internal.example.com and two.internal.example.com on route53, while still managing example.com and the rest on Cloudflare.

According to this answer, I understand it's possible to manage one sub-domain on different nameservers, but how do I manage multiple sub-sub-domains?

Am I forced to create a nameserver entry on the TLD (Top Level Domain) for every sub-sub-domain or can I use a wildcard or some other method to only add one nameserver entry on the TLD?

Answer 1

I figured it out, all you have to do is add records like these on your TLD, as the original question suggested:

internal.example.com. 1799 IN    NS  ns1.second-nameserver.org.
internal.example.com. 1799 IN    NS  ns2.second-nameserver.org.

After that, any DNS entry that ends with .internal.example.com, such as one.one.internal.example.com or two.internal.example.com can be managed by the second nameserver, no extra configuration needed.