Redirect request to external DNS if record not found

[aleksey-samuylik-idf]

Can you please tell me how I can implement a script on dnsdist or recursor lua that will perform a preview of domain records and, if it doesn't find them in pdns-auth, send a request to an external public dns server, e.g. 1.1.1.1
That way we don't have to keep adding domains to the dnsdist and recursor configuration files.
Ideally I see a query to dnsdist, it checks the record in pdns-auth and if the response is NOERROR it sends it to the client, if the responses are NXDomain, REFUSED, SERVFAIL it sends it to the external dns server and the result of the response to the client.
Example:
A private dns has a public domain
xyz.com and an A record in it:
Name: bastion.xyz.com
Address: 10.86.10.10
The public dns has no fqdn data, but has other public A records.
The task is to resolve the private fqdn in the private dns, if it doesn't find a matching record, redirect it to Cloudflare's public DNS