If a folder editor removes files from the folder, if those files doesn't belong to any other folder they become "orphan" files. See How to view orphans in Google Drive
Also the folder activity panel should include a link to the removed files.
The way to restore the files is by adding the files again to the corresponding folder either by using the Google ...
Go to Who is my administrator?
NOTE: The above link points to a tool on the G Suite Administrator Help Center that could show who is the administrator of the account used by the user who is accessing the web page.
This is what is shown for one of my accounts managed by someone else
Who is my administrator?
Quick definition: A person who manages ...
It's not possible to be an admin without being a user as it's necessary to be an user to access the G Suite admin panel to manage the organization settings.
You could confirm this with the G Suite Sales team.