Hi @Colin Lewis ,
Unfortunately, after my attempts, there is no way in SharePoint Online to set a column to be edit/confirm only for some users (deemed to be managers), while other users have CREATE permission. This is because other users with CREATE permission (i.e., edit, etc.) can edit the column.
And the smallest permission level in sharepoint is item, you can't set it for smaller column levels.
I think maybe you can go to Power Apps Community and post a thread to see if you can accomplish what you want with a Power Apps custom list. Hope this information can help you!
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