Problem converting singlesite to Multisite

Today we have done a modification to
This site was running wordpress simple and we configured it to be
converted to multisite.
The client needs to have these multisites: (original site) (new site) (new site) (new site)

i have gone through the instructions here:

It seem that it's working ok as it is shown here:

but the problem is that it cannot resolve these domain names:

Any suggestions on how to fix that so that when i click on a multisite it doesn't bring a 404 page ?

Probably a problem with the .htaccess ?