Migrating Site to Multisite - How to get images and users to transfer


I am trying to migrate a WP site into my Mulitsite. I followed these instructions: https://premium.wpmudev.org/blog/migrating-multiple-blogs-into-wordpress-multisite/

All of the pages and posts transferred but the images and users all got errors. Is there some way that I can transfer just the images and users now that the content is already there?