multisite subdirectories with non-wp sub sub directory?

wondering if it is possible to have a setup with Multisite for subdirectories like :

https://www.example.com
https://www.example.com/site1/
https://www.example.com/site2/

but then have a subdirectory inside one that is not WordPress, someplace like

https://www.example.com/site2/outside-of-wp/

Would there be some .htaccess trick(s) to make /site2/ still function as its proper site inside the Multisite, while /site2/outside-of-wp/ is autonomous all on its own?

Or with Multisite subdirectory method, would any extra non-WP subdir have to be from root level, like

https://www.example.com/something-outside-wp/ then?

I hope I managed to explain the situation right? Thanks for any advice!