No, it is not the same solution. If you see this topic, you gave me a code (https://gist.github.com/generatepress/c23aef2d05807c39bb32) to get appear the toggle menu for a specified width. But with the secondary menu the problem with that code is that the elements are showed even when the toggle is not pressed.
In my web, the problem is showed between 768 to 850px. You can check narrowing the window in my web, or you can see a screen shot of the problem: http://econactiva.es.mialias.net/wp-content/uploads/2016/01/screen-shot-secondary-menu-problem.png
I hope the issue is more clear. Thank you in advance.