@Mathew Henderson You should work with your Docebo implementation team; they might have some options for you.
When I migrated to Docebo, I decided to create a series of course shells that I called “Equivalent from Old LMS”. For each learning plan or course that I wanted to maintain records in Docebo, I created one of these shells and assigned them to the migrated learners. No training materials, just the shell. All of these course shells were marked as “completed”.
Then I set this course shell as the equivalent to the new Docebo version of these courses.
I did a lot of planning via spreadsheet, and used batch .csv files to make it all happen with less clicking.
Good luck! Happy to discuss more if you need.