How to get authorization code when admin adds user app?

API Endpoint(s) and/or Zoom API Event(s)

Description
I have a team chat user app that installs successfully when the user authorizes the app. They are sent to the redirect_uri with the authorization code, which I use to get the user token and refresh token. It works great.

The error I’m running into is when an account admin for the user authorizes the app for the user (per How to add Marketplace Apps as an admin).
When the admin authorizes the app, the redirecdt_uri is never called, so my app doesn’t recieve the authorization code for the user, thus no access token. I need to the token in order for the app to function and make calls to the OAuth endpoints.

I can’t find any documentation that addresses this issue.

How can I get the users authorization code when the app is added by an admin rather than the user?