Read this article to how safe is your users’ and company data during the installation of Form Publisher for your domain.
Difference between installation by Individual vs Google Workspace Admin
An individual can install Form Publisher from Google Workspace Marketplace or Chrome Web Store page. During installation, the user will be asked to authorize a set of permissions that are needed for Form Publisher.
As a Google Workspace admin, you can also pre-install and pre-authorize Form Publisher from Google Workspace Marketplace, for all your domain users. Your installation for domain-wide use is one-time and makes Form Publisher readily available for all your users.
You authorize and grant the same set of permissions as in an individual install, but you do it on behalf of all your users as well. So when the users want to use Form Publisher, they don't need to authorize it again individually.
Does your permission for Form Publisher allow it to have access to all your user’s data?
We cannot impersonate your users and retrieve their Drive/Gmail data, programmatically.
We can retrieve their data only when a specific user interacts with Form Publisher add-on. This behavior is as if he has installed and authorized Form Publisher himself.
Is your company and user data at risk?
Unlike many other Google Workspace apps, Form Publisher doesn't ask to create a 'service account with domain-wide delegation'. It means that Form Publisher doesn't access users' data who aren't using the product.
Can I whitelist Form Publisher instead of domain-wide installation?
OAuth apps whitelisting is to specifically allow selected third-party applications to access your users’ Google Workspace data.
Form Publisher is neither a Google Workspace web application (it is an add-on for Google Sheets) nor does it ask for access to your users’ data (via domain-wide delegation of authority).
So whitelisting is not applicable for Form Publisher.