Allow admins to customize the page customers see when trying to access a survey that was already submitted
When a customer click on a link for a survey that has already been submitted, a customer sees the following page:

Even if in Survey > Design you have enabled “Hide Powered by Gainsight” footer, it still shows this page.
Even if you create a custom Page in “Pages” with your own header, footer, and content and use that as your Thank You configuration page in Survey Design, it still shows this page.
From Support:
Thanks for reaching out to support! Currently, it isn't quite possible to remove that from our surveys as it is hard coded in.
With the push for digital CS and the bionic CSM, Gainsight needs to do more for giving us customization and features that allow for whitelabeling our surveys and any other external asset.