I am distributing TWBX files to Tableau Reader users and some, not all, get error messages looking for the .tde in their temp folder. My data source in Tableau Desktop is an extract from Excel, not live connection. I "Save As" TWBX and then distribute. Again some have the issue and some don't, however they are all using the same versions.
Though I'm not sure about Export Packaged Workbook and Save As Difference-Tableau Desktop ,
anyway please also have a try at
File -> Export Packaged Workbook...
to see if the error still happens.