https://fluentforms.com/docs/fluentform_email_template_after_footer/
fluentform/email_template_after_footer - Fluent Forms
This hook runs after rendering the email footer. You can use this to insert anything in the footer.
email templatefooterfluentforms
https://wordpress.org/support/plugin/gsheetconnector-for-fluentform/reviews/
[GSheetConnector for FluentForm] Reviews | WordPress.org
reviewswordpress