Integrating with a crm

I am using a CRM with WordPress where they are connected by a plugin with PHP and javascript. I want Anonymous visitors to authenticate under DIFFERENT conditions: Time, URL, number of specific events in a session or across sessions. There are a lot of if then conditions, because if this is done in a one-approach-fits-all I might piss off an otherwise converting lead. I do not want the authentication to update WordPress, but rather only my CRM. Is there a way to do this, or am I forced to add a WordPress user account for each authenticated person? I see where to authenticate against LinkedIn and Facebook, but not how to achieve that with my CRM. Where do I define the conditions under which I present an unauthenticated visitor with a login? Google Tag Manager?

Any hints and help would be great