using custom repository via AutoYast is not employed

SUSE Linux Enterprise Extensions SUSE Linux Enterprise Server
1

I’m exploring maintaining a private repository, and am trying to employ it via AutoYast, all under SLES 12 SP 5.
I’m hoping someone can provide some guidance.

I added this to my autoinst.xml file:

  <add-on>
    <add_on_others config:type="list">
      <listentry>
        <media_url><![CDATA[http://10.153.19.116/repo/]]></media_url>
        <product>Example Product</product>
        <alias>example</alias>
        <product_dir>/</product_dir>
        <priority>30</priority>
      </listentry>
    </add_on_others>
  </add-on>

But, when I also declare a package from that repository to install, YaST throws errors:

2020-06-18 17:31:15 <3> install(18178) [Ruby] modules/AutoinstSoftware.rb:1096 Cannot select following packages for installation:
2020-06-18 17:31:15 <3> install(18178) [Ruby] modules/AutoinstSoftware.rb:1099   java-13_0_2-openjdk : The package is not available. (selected by AutoYaST configuration file)

And I see no evidence that YaST attempted to process my repository in the logs.
I can confirm repository has the package:

localhost:~ # zypper addrepo http://10.153.19.116/repo/ example
Adding repository 'example' ..............................................[done]
Repository 'example' successfully added

URI         : http://10.153.19.116/repo/
Enabled     : Yes
GPG Check   : Yes
Autorefresh : No
Priority    : 99 (default priority)

Repository priorities are without effect. All enabled repositories share the same priority.

localhost:~ # zypper pa -ir example  | grep java-13_0_2-openjdk
v  | example    | java-13_0_2-openjdk             | 13.0.2-8.2                               | x86_64
2

I finally got help on this topic from the opensuse-autoinstall list; the add_on_others feature was introduced in SLES 15, and I needed to use add_on_products instead:

  <add-on>
   <add_on_products config:type="list">
      <listentry>
        <media_url><![CDATA[http://10.153.19.116/repo/]]></media_url>
        <product>Example Product</product>
        <alias>example</alias>
        <product_dir>/</product_dir>
        <priority>30</priority>
      </listentry>
    </add_on_products>
  </add-on>