Users Not Showing in User List after batch create

Hello - I was able to successfully batch create all my users using your awesome plugin, but I noticed now that after doing so that either via my Site Admin or Network Admin (using WPMU) none of the users show in the list (see screenshot).

I wanted to edit some users to make them contributors and discovered that I cannot change their roles. So at first I was confused and I tried to add 'existing user' to site giving them Contributor roles but it said the user was already a member of my site, even though I can't see them in the list.

When I setup my batch create file I used the following values in my spreadsheet:

null null Username null EmailAddress Member

I'm just not sure why I'm having this error? Did I do something wrong?