Thank you very much.
I tried it and it works. And to show a specific menu, after trial an error, the following code worked for me:
{% set args = { menu: 'Secondary Menu' } %}
{% set menu = mb.wp_nav_menu( args ) %}
The menu can be specified using the ID or name.
So in the end, I used the bit of code you wrote to show the main/primary navigation, and then this second example to show the secondary menu.
But I want to check, please: is this the correct way to target a specific menu on MB Views?