How do I display widgets for a specific group of related pages, categories and posts?

I’m creating a site that needs to have widgets displayed in a very specific way. For example, I would need a Recent Posts widget that would be displayed on:

-Page: Marketing

-Category: Marketing

-Post: All child posts of the Marketing category

I’m using the WP StartBox framework with a child theme. I have tried several plugins (Display Widgets, Custom Sidebars, Widgets Controller, Widget Context, Shiba Widgets) and have had zero luck getting them to display the way I want.

StartBox has it’s own custom sidebar tool, but that didn’t work very well either.

The best I’ve been able to do is get the widget displayed on 2 of the 3 places I need (page & category).

One thought is that the fact that many of the posts on this site are listed in more than one category. I’m not sure if that’s confusing the plugins.

I’m starting to think a conditional is the only way to really do this. Any suggestions?