BuddyPress.org

Also, I don’t see how this will specify it to be underneath the random blogs listed on the blog directory in the right column.

This is the magic:

add_action('bp_after_directory_blogs_featured', 'my_custom_content_after_random_blogs');

This tells the “bp_after_directory_blogs_featured” do_action part of code in /wp-content/themes/bp-sn-parent/directories/blogs/index.php to plug in your custom code.