trouble getting multiple domain filtering working

https://deliciousbrains.com/wp-offload-media/doc/filtering-urls-for-multiple-domains/

I am reviewing the example, however the example only shows a subdomain set up instead of a subfolder set up.

for my domain[1] string how should it be set. I have tried:
networkdomain.com / subfolder /

which is not working…should it be:

networkdomain.com / subfolder (no forward slash)

does it matter if I have https:// on the front part?

Thanks!