Certain roles creating users I am spinning up a site that will have 18 different organizations interacting together.  Each organization has a president with access to specific forms and parts of the site.  I would like them to be able to create/add users from their own organization.

Where I am stuck is that each president should only be able to edit/remove users from his own organization (aka that he created).  Do I need to create 18 different roles for each president and 18 different roles for members from their organizations, or is there a more convenient way of managing this.

I have reviewed the following modules without success:
Protect_critical_users, role_delegation, administerusersbyrole

Thanks.
You need not to create different roles for each user but one user role will serve the purpose with help of SUBUSER module.
Though it's in alpha stage for D7 but it has served me well for a project where I am handling organization as users.
You will need to give proper permission though, I hope you can play with that.