How do you setup the catalog zone in BIND9?

Question

I've been trying to setup a catalog zone in BIND9 so that way I do not have to manually update my slaves each time I add or remove a domain.

I asked this question and the answer would be to use the catalog feature of the new version of BIND.

I tried to follow whatever I could find online but that wasn't much at all and nothing about debugging your catalog installation properly.

Master DNS

On my master I added the following settings in main.conf.options:

zone "catalog.example.com" {
        type master;
        file "/etc/bind/catalog.example.com.db";
        allow-transfer { trusted-servers; };
        also-notify { slave-servers; };
        notify explicit;
};

Note: the trusted_servers and slave_servers are ACL definitions such as:

acl trusted_servers { 10.0.0.1; 10.0.0.2; };
acl slave_servers { 10.0.0.2; };

The zone itself, /etc/bind/catalog.example.com.db, is special as well, it includes a version and the NS entry is invalid:

; catalog.example.zone
$ORIGIN .
$TTL 86400
catalog.example.com.    IN SOA  . . (
                1       ; serial
                3H      ; refresh
                180     ; retry
                1D      ; expire
                300     ; default_ttl
        )
                        NS invalid.

$ORIGIN catalog.example.com.
version                 IN TXT "1"

That way the version can be checked from any BIND server.

Slave DNS

On the slave server, I added a couple of settings in the options block:

options {
    ...
    allow-new-zones yes;
    catalog-zones {
        zone "catalog.example.com" default-masters { 10.0.0.1; };
    };
    ...
};

Just in case, I also made sure I had the following options:

    allow-recursion { any; };
    allow-query { any; };
    allow-notify { trusted-servers; };
    allow-transfer { trusted-servers; };

Would I also need to setup the controls entry to give the master control of the slave?

Next I created a catalog zone on the slave with the following:

zone "catalog.example.com" {
    type slave;
    file "/var/cache/bind/catalog.example.com.db";
    masters { 10.0.0.1; };
    allow-notify { 10.0.0.1; };
};

That zone does transfer. I can see the data (same as what I have above appears in the cache).

Issue

As a result I get errors like this one

19-Apr-2020 13:07:39.124 notify: notice: client @0x7f42548c18b0 10.0.0.1#44622: received notify for zone 'm2osw.com': not authoritative

This happens for all the zones, except the catalog zone.

When using the regular setup, I have entries like so:

zone "m2osw.com" {
        type slave;
        file "/var/cache/bind/m2osw.com.zone";
        masters { 10.0.0.1; };
        allow-transfer { none; };
};

and I know that by not putting the masters ... field I get that error (not authoritative).

I fail to see how I could make a zone that I want to automatically be transferred explicitly authoritative.

Can someone enlighten me in the endeavor of setting up a catalog zone?

The only one thing I can think of is that I would need to setup a key properly. I've tried that but so far I only managed to completely block my master DNS. Some clarification on this setup process would be really wonderful!

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Note: The IP addresses correspond one to one to what I have on my servers, only of course my servers make use of public IPs.