Hi Jarom,
Content Matrix cannot migrate deleted or disabled users from a source to a target environment. You may refer to the article below for a workaround:
Authorship columns show migration account on target
metalogix.force.com/.../Authorship-columns-show-migration-account-on-target
Regards,
Cyrus
I understand the work around, which is reason for asking why this is the case. What is the limitation on how Content Matrix works? Why does it need an active user account?