Yes, the admin can upload the documents on behalf of the applicant(s) from the Manage Applicants screen. Please follow the below steps to do so.
Step 1: Click on the application name from the Home screen for which you would like to update the answer or upload the file for any of the users.
Step 2: From the Manage Applicants screen, search and click on the user name or the organization name to access the dashboard.
Step 3: Click on the section name under which you want to upload the document(s).
Step 4: Upload the document and click on Save & Return to Dashboard at the bottom of the section page.