Lightsail DNS Subdomain Mapping To External Domain

Good evening.

The domain we wish to use with a Lightsail instance was bought via Google Domains and is being hosted with Google's Cloud DNS.

The domain has tons of services attached to it (including DNSSEC) so moving the DNS records is not ideal for now.

We certainly will move it to Route 53 given that Google has decided to play chickens with Squarespace and left its customers that trusted them in the dust.

We have used domain assignment to point a sub-domain for the instance to the Lightsail instance.

Have added the IPs to the domain's records at Cloud DNS.

But have chosen not to use the Lightsail auto-generated name servers.

My question is, does mapping a sub-domain to a Lightsail instance require using the Lightsail or Amazon Route 53 issued NS?

I'm unable to find the answer at either:

• https://lightsail.aws.amazon.com/ls/docs/en_us/articles/amazon-lightsail-using-route-53-to-point-a-domain-to-an-instance or
• https://lightsail.aws.amazon.com/ls/docs/en_us/articles/amazon-lightsail-point-domain-to-distribution or
• https://lightsail.aws.amazon.com/ls/docs/en_us/articles/lightsail-how-to-create-dns-entry

Thanks for the leg up!