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If you have the Plus plugin, you can insert the Site Title and tagline inside the Menu Left HTML boxes either manually or using their respective shortcodes (see Xtreme Admin > Add-ons page).
Without plus you could do that in the right HTML box.
Alternatively you could create an Image of the Site title and tagline and set that as your Site WP Custom Logo, and display the logo in the menu bar.
We can also move the menu bar over the header, but that would require some custom CSS and we would need a link to your site to have the full picture.