cross domain tracking not reflected in navigation summary - google-analytics

Question

edit
I edited my post as I narrowed down the issue to just different domains; sub-domains are not an issue.
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In google analytics there is a navigation summary that shows the previous and next page paths for any page path in the property. This report is under the behavior tab > site content > all pages > navigation summary at the top.
I have cross domain tracking set up but when I go to the navigation summary report I do not see any traversal between domains. The only activity is between subdomains and within the same domain (i.e. www.example.com, a.example.com, b.example.com but not www.anotherexample.com).
I know there is traffic happening between domains because I have done it myself and watched my own session in the real-time tab as I went between two different domains, sometimes including URL parameters to single out my own session.
Why can't I see cross domain tracking in navigation summary?
JS on domain1.com:
(function(i,s,o,g,r,a,m){
i['GoogleAnalyticsObject']=r;
i[r]=i[r]||function(){
(i[r].q=i[r].q||[]).push(arguments)
},i[r].l=1*new Date();
a=s.createElement(o),
m=s.getElementsByTagName(o)[0];
a.async=1;
a.src=g;
m.parentNode.insertBefore(a,m)
})(window,document,'script','//www.google-analytics.com/analytics.js','ga');
ga('create', 'UA-XXXXXXX-YY', { //this uses my real tracker ID
'name':'a',
'allowLinker':true
});
ga('require', 'linker');
ga('linker:autoLink', ['domain2.com']);
ga('create', 'UA-XXXXXXX-YY', {'name':'b'}); //Again, uses my real ID for a separate property
ga('a.send', 'pageview');
ga('b.send', 'pageview');
JS on domain2.com:
(function(i,s,o,g,r,a,m){i['GoogleAnalyticsObject']=r;i[r]=i[r]||function(){
(i[r].q=i[r].q||[]).push(arguments)},i[r].l=1*new Date();a=s.createElement(o),
m=s.getElementsByTagName(o)[0];a.async=1;a.src=g;m.parentNode.insertBefore(a,m)
})(window,document,'script','//www.google-analytics.com/analytics.js','ga');
ga('create', 'UA-XXXXXXX-YY', { //uses my real tracker ID
'name':'a',
'allowLinker': true
});
ga('require', 'linker');
ga('linker:autoLink', ['domain1.com']);
ga('create', 'UA-XXXXXXX-YY', {'name':'b'}); //uses my real tracker ID
ga('a.send', 'pageview');
ga('b.send', 'pageview');