Hi Sam,
I do have the pbix file because we were the ones who created the template app for our users. However from a user point of view, they cannot download the pbix file directly from the report in PBI service as it is greyed out. This link to connect to the dataset was a workaround/ hack to download the pbix file from the template app .
I guess the initial question would be , is it possible to give end users the ability to download the pbix file from template apps (with the data model and connecting to other data capability)?