If anyone else is looking for a solution to import users into WordPress and also add them to LearnDash courses, this plugin won’t do it – at least according to LearnDash support, it won’t.
I was able to use the plugin to import users into groups with the help of this doc ( https://bitbucket.org/snippets/learndash/Aroxx9/import-users-via-csv ) but that’s because importing into groups is relatively straightforward in terms of the integration with the database.
Importing into courses is more complicated and I ended up buying the Uncanny Owl Toolkit Pro for this purpose and it’s very solid. It really deals with the challenging database stuff very well. I didn’t want to pay $150 for a plugin just to import students into courses but I didn’t find anything else (there were a couple of less expensive plugins I came across for this purpose but their reputations weren’t great).
By the way, if you already have your users and you just need to add them to LearnDash, both plugins work for that, but again, this plugin only works for groups whereas the one I bought works for groups and courses.
Oh, if you really want to avoid paying the money, what you could do is create a group for each course and then use this plugin to import the users into those groups. But you can’t delete the groups, so it’s kind of an annoying workaround.