Kaitlyn,
When you say you have Tagalong and Power plugins….Power disables Tagalong as the functionality that was in the Tagalong legacy has been revamped and part of Power.
First, you are confusing Tags with categories.
they aren’t the same thing Here is the explanation in the documentation site TAGS VS CATEGORIES.
Formats: examples CSV
Locations Imports Headers
If you have multiple categories for one location , in your excel file separate with a comma.
You would just have in the header row the word Category or Categories.
You can have both tags and categories assigned to each location juts be aware they are different. Tags is just text, no parent child heirarchy.
Category Import