A referral must come from your primary care provider and as of yet, I can't get them to write me a script for an escort.

References have been required for ever.  Being on and off can present a problem, as most of the girls you have seen may be long gone.

My advice to you is to join a verification site.  Most providers will use them

I have been participating in the reference system for three years.  It was definitely already happening, when I showed up in this scene.  (By the way, I learned about TER from another provider, who used references, too.)

My advice to you is to join one of the screening websites that most of the providers use.  Or, go along with a provider's screening, if you want to see her, if she seems discreet.  

There are providers out there, who do not screen new clients, but many people would argue that is a riskier situation for all parties involved.