First off - thank you for the workbook. This is version 10.3 for others trying to help.
The views use three data sources.
The data sources are linked in Tableau using Data Blending.
First question - Does the data need to be in three seperate sources? Where is it's origin and could they all be in the same source (for instance an Excel workbook) to allow for using Joins rather than data blending?
The sorting question -- I am not following this question in the description. Could you provide a few exact steps .. do 1, then do 2, etc.. so we can follow along and better understand the desired behavior vs what is occurring.