Views conditional referenced field depending on user taxonomy term
I believe your explanation is describing the Reference Field Option Limit module:


  This module allows reference fields of several types to have their
  widgets' available options limited by the values of other fields in
  the current entity.
  
  This is best illustrated by examples:
  
  Example 1: countries and cities Suppose you want to label articles (or
  products, or businesses, etc) by both city and country so both can be
  used for filtering and searching. You could use a hierarchical
  taxonomy with city terms as children of country terms, but that
  doesn't make sense when you come to set up Views filters.
  
  With this module, create two separate taxonomies for country and city
  (or content types, or whatever entity you want to use). Then add a
  reference field so that each city points to its country: eg, the term
  'Paris' has a reference to 'France'.
  
  Then when editing an article, selecting 'France' in the country field
  will cause the city field to update to show only cities in France.


Give it a try and let me know how it works. The module currently supports Taxonomy terms and Entity Reference Widgets.