I think I understand pretty well what it is you are seeking to do. When you bulk invite using CSV, each email address in the CSV file is sent its own unique invite link that only works for that email address. And if specified in the CSV is also added to one or more groups and sent to a topic. It’s a powerful feature!
I would suggest you try this out for yourself to make sure you are comfortable with how it works, and then to invite people in smaller batches instead inviting a large number of people in one big bulk invite.