How to use omniauth-google-oauth2 with a domain and subdomain in rails7?

omniauth-google-oauth2 works fine on the main domain, I have this folder structure:

controllers/auth/google_oauth2_controller.rb

inside google_oauth2_controller I'm using module Auth:

module Auth

    class GoogleOauth2Controller < ApplicationController

    ...

    end
end

my routes.rb:

 namespace :auth do
      namespace :google_oauth2 do
        get "callback"
      end
  end

The above works fine for the main domain, when I want to do the same for a subdomain, I'm having problems, because I have to also do another controller with the same name and folder name like so :

controllers/auth/google_oauth2_controller.rb

but the content is different because it redirect to the subdomain. Is there a way to structure this so they don't have conflict?