Set up a Gravity Form (in this case, form ID 1) to be sent from one user to another, by repurposing the "save and continue" button.

gravity-save-continue-two-users.php

<?php

add_filter( 'gform_savecontinue_link_1', 'prefix_savecontinue_form_id_1', 10, 2 );
/**
 * Maybe remove the "save and continue" button from Gravity Form ID 1.
 * Checks to see if the "save and continue" token is present--
 * if no, the button will render, otherwise not.
 *
 * @param string $save_button
 * @param object $form
 * @return string
 */
function prefix_savecontinue_form_id_1( $save_button, $form ) {
	if ( prefix_does_token_exist() ) {
		return '';
	}

	return $save_button;
}

add_filter( 'gform_submit_button_1', 'prefix_submit_form_id_1', 10, 2 );
/**
 * Maybe remove the "submit" button from Gravity Form ID 1.
 * Checks to see if the "save and continue" token is present--
 * if yes, the submit button will render, otherwise not.
 *
 * @param string $button
 * @param object $form
 * @return string
 */
function prefix_submit_form_id_1( $button, $form ) {
	if ( ! prefix_does_token_exist() ) {
		return '';
	}

	return $button;
}

/**
 * Check to see if the second user is viewing the form (based on whether the Gravity Forms token is present).
 *
 * @return boolean
 */
function prefix_does_token_exist() {
	return (bool) filter_input( INPUT_GET, 'gf_token', FILTER_SANITIZE_STRING );
}