IF OBIEE is configured using Active Directory then how you can expect to add user using weblogic. Add users to active directory group and those users will show up in weblogic.
I am not trying to add users but edit the permissions of the users in BI by adding the existing users to a new group because currently everyone that logs in is defined as a consumer. From my understanding and readings it said that you have to first define a group in web logic to add the users to and than define the permissions of that group on enterprise manger.
In essence I am trying to update the permissions of select users in BI without having to change the configuration active directory.
Hope that makes it clear.
"In essence I am trying to update the permissions of select users in BI without having to change the configuration active directory."
Rather it is a better approach to add users to AD groups that represent their BI roles then import into WLS and map to application roles in EM. ArijitC has shown you the proper way. This way you can use your corporate access request process to have people added to appropriate groups and thus roles without another step in the process. Less likelihood for error.
You already got the best answers above, so I just want to point out few details.
You don't have to add a user in a group and than assign that group to an application role. You could directly assign the user to the application role if you want, but as they said above using a group is a good practice (because users can join or leave or change role in your organization, so managing it directly in AD is easier).
If you can't (for organizational reasons) add users in AD you can consider also using a database to provides the mapping between users and roles (keeping authentication of the user on AD).
But the best practice is what they posted above