The answer is Yes to creating a wiki article linked to a custom pages (you can do it for generic inquiries too). We have many configured this way.
I created my first wiki article linked to a GI (should be same for custom page) by doing the following:
- Make sure your custom page or GI is in the sitemap
- Create the wiki article using the name of the page as you have done ("PO_30_99_99" for example). I also set the wiki article name to the same name as the sitemap entry title - but not required.
- The wiki should now be linked to the new article.
You might want to try these steps over again by deleting the article you are having trouble with and trying again to make sure the correct references are auto generated by Acumatica. This could be a problem if you created the wiki article before your sitemap entry existed.
As Needed: The person that does our articles sometimes goes into SQL to changes some values to get things to work (could be old habits as the wiki packaging was improved over previous versions). You can do this via export of the article, modify the xml, and re-import if needed without going into sql. This assumes you want to keep your current article. Otherwise should be able to in the UI.