locking column in pivot table without data

In pivot table I need to lock a column (header) so if there is no data in that column, it doesnt remove it from table (and the chart). Now this is easy if i am using simple pivot table, but when using Data Modeling, the option to show columns without value is greyed out. I know there is a way around it but not sure how to do this? Please help. I am not a programmer and need a simple solution to go about this. Im using excel 2013

Here is an example datasheet. If you click on all sources in slicer datachart is fine, when you click on any one source, the "open" column disappears because it has no data in it
and then the chart goes wrong.test.xlsx