Hi @auth0-discovery,
You can use a rule to assign roles. Here is an example of using a default role: How do I add a default role to a new user on first login?
You could also add emails to a list when their invite is sent and then look up the list of users/required roles when they log in. You could call your own API to track expected users/roles and call it within the rule or you could use this example that uses a dropbox-hosted file to keep track of users.