Hello Waseem

Unfortunately, if you leave the drop-down at "Any Employee", the plugin will assign him (her) randomly. There's no way of forcing the plugin to assign appointments to employees in that way.

Hello again Waseem

I suppose you simply hid the "Employee" drop-down from front end, correct?

If that is true, then yes - it would work the same.

The only other way you don't see the employee dropdown would be if you have only one employee, and in that case, this issue doesn't exist.