Validation message not allowing confirmation message

// Tie our validation function to the 'gform_validation' hook
add_filter('gform_validation_9', 'validate_donation');
function validate_donation($validation_result) {

	// Make a call to donate.php validation function to validate the donation
	$is_valid = process_payment();

	// If the payment is valid we don't need to do anything
	if($is_valid){
   		// Return the validation result
    	return $validation_result;
		}
	else{
		// Fail the validation for the entire form
		$validation_result['is_valid'] = false;
   		// Return the validation result
    	return $validation_result;
		}
}

// This function runs the Donation script for eTapestry/SAGE
function process_payment() {
    include("donate.php"); 	//this is the processing of the online donation
}

// This function changes the main validation message
add_filter("gform_validation_message_9", "change_message", 10, 2);
function change_message($message, $form){
global $donate_error;
 	return '<div id="donate_error">' . "An error occurred while processing your submission.<br/>Please modify your information based on the error below and try again.<br/><br/>" .  '<span>' . "Error: {$donate_error}" . '</span>' . '</div>';
}