gistfile1.php

// in theme functions.php

<?php
add_action('gform_after_submission', 'createPaymentForm', 10, 2);
function createPaymentForm($entry, $form) {
    
    $valuesFound = false;
    $fieldId = -1;
    $fieldTotalId = -1;
    $fieldCounter = 0;
    
    foreach($form["fields"] as $field)
    {
       $fieldId = ($fieldCounter == 1)? intval($field["id"]) : $fieldId;
       $fieldTotalId = ($fieldCounter == 2)? intval($field["id"]) : $fieldTotalId;
       
       $fieldCounter++;
       
       if ($fieldId > -1 && $fieldTotalId > -1) { $valuesFound = true; break; }
    }

    if ($valuesFound)
    {
        echo 'markup for your form';
    }
}

?>