Hello Earl-
The theme in your screenshot has three columns, and you’re right that none of the BoldGrid themes support this. There are many three-column themes available for free on WordPress.org that might be able to accomplish what you need.
It does look like a lot of the content in your screenshot is being provided by different widgets. For example, the “Forum Updates” looks like it’s probably a recent posts widget, and the events on the left would be provided by an events plugin.
You can use BoldGrid’s Post and Page Builder, along with all our other plugins, with most 3rd-party themes.