Adding non related fields to Paginated Report visual

I have created and published a Paginated report where one of the Parameters is a list of tablix column names and I used this to allow the user to select which columns are displayed or hidden.  This works fine.

Now trying to add this as an embedded visual in a pbix report but when I add this column heading field to the visual it creates an error as there is no relationship between this and the other fields.

In my mind there doesn't need to be a relationship as these fields will just be used as input to the Parameters in the Paginated Report and as a source for the slicers.

Am I understanding this in-correctly or does there need to be a relationship?