Some bookers do this, and P411 used to do it at least when I joined many years ago.  

If you have a public presence on the internet as an employee, you can send links. If not or if you don't want to provide such links, there is a discrete but effective way of doing it. You give them the number of your organization's main number and ask to be connected with the or get a direct number. Once the receptionist transfers the call or gives her the direct number, she knows what she needs for verification and can hang up before you realize that you have been verified that way.

I have NOT done the employment route, but she should explain to you her general procedure.
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For example, she calls main number; asks reception (or voice menu) for Mr. izzmeblink; if she gets a live person that isn't you, she says it's the dentist's office calling with a reminder about his appointment (or something like that). There are other variations. She should know that the first male voice she hears might NOT be you (you might have a male assistant / sec'y), and should NOT blurt out "This is your fuck toy calling to confirm that you're hard for me." "This is Mr. izzmeblink's assistant. I will give him your message. Who shall I say was calling?"

Or at least she said she did.  This was before I was on p411.  In fact, she introduced me to p411 after.

What the hell are the providers thinking when they pull this type of bullshit?!!  Seriously !!!  We all have to be discreet in this line of work.

High hurdle that many won't cross. But, it was the price of access to premium k-talent.

This was despite me having P411 with employment verification.

Is No!
The further answer to your question is not even when if Margot Robbie is offering to let me bone her in the butt, Scarlett Johansson is offering to be a 3rd, and pigs are flying on a cold day in hell.

I only hobby with those who conform to what I consider reasonableness in verification..  

 
Remember, I am the boss here.. I pay them..  Don't let the women wear pants.. They will walk all over you.

Some years ago an escort wanted to verify my place of employment prior to meeting me.  I told her that I was out in the field and seldom went to the office.  She said that she would call the office and leave a message reminding me of a doctor appointment.  I said okay and gave her the name of a fellow worker who also worked out of the office.  She called, there was a verifiable employee with that name and the receptionist took the message.  Escort was satisfied and I kept the appointment without giving her my real name.

Forgot to mention in my post that the fellow worker whose name I used was young and single.