I am trying to create a column that will display a person or group content type (with active presence displayed) for all Active Directory users and/or a single line of text for all inactive users no longer in Active Directory. The inactive users are needed to migrate historical records to the new SharePoint list. These items will are often searched and referenced. The person/group content type for active users will be used for audience targeting, specified views, permissions, and workflows.
Ideally, the column would allow select from 2 content types, but based the research I've done over the last few days, it appears that this is not something that can be done (at least without additional programs/add-ins which are not a viable solution at this point). My other thought was to have a column display based on condition, ie, if column X contains display value from Column X, else display value (choices) from Column Y. I am not sure how one would do this for an input field.
I am a relative newbie, so it is possible that there is something simple that I am overlooking. Any advice on the best way to proceed (and or links to how to articles) would be greatly appreciated.
THINGS TRIED SO FAR: I have tried using a multi-field look-up, which only returns a single line of text. I"ve looked into creating custom site content type, but do not know too much about implementing this and have not been able to set a column to the new content type containing both text and people/group.