Google Drive documents can be embedded in Google Sites.
This document explains how Cloudiway proceeds to migrate those sites and explains the prerequisites.

What is the problem?

Google Site stores the URL of the Google Drive documents embedded in the site.
The URL contains the Google Drive IDs but does not provide any information about the owner.
All we get is the Google Drive ID of each document and from it, it’s not possible to determine the owner or to give permissions to the migration account.

Google Drive Ids

What is the solution

Use Cloudiway Site Migration and Cloudiway File Migration together.
During the migration or the audit of the Google Drives (Cloudiway File Migration), Cloudiway platform builds a list of all Google Drive IDs and their respective owners.

From it, Google Site migration is able to determine the owner of each embedded Drive document.
The platform can now impersonate the owner and access the document.

Summary

If you do not use Cloudiway Site Migration and Cloudiway File Migration together, the Google Drive documents embedded in Google Sites will not be migrated.