HI, I am having the exact same ubermenu issue that another user posted about a week ago, and so I followed your suggestion with using the shortcode and the problem did not fully resolve- the ubermenu shows up now but the styling is not carrying over completely to the first 2 main pages-the font displays in the wrong color, but the correct styling does show up in the subs of those two pages in their respective dropdowns. Also, what is showing up in the sandbox is an incomplete version of the same menu.
I’ve gone through all suggested troubleshooting options - spent an entire day doing so- and have not been able to fully resolve the issue, so I am asking the experts. Beyond the shortcode approach, I am clueless as to where to enter the code that will manually override the theme navigation.