Dynamically Generate Unique URLs from Gravity Form Inputs with Query Parameters

// Enter the ID of the form at the end of the 'gform_confirmation_ID' filter
// In this example, the function will only run on the form with the ID of 1
add_filter( 'gform_confirmation_1', 'fivetwelve_custom_url_confirmation_queries', 10, 4 );
function fivetwelve_custom_url_confirmation_queries( $confirmation, $form, $entry, $ajax ) {
    if ( isset( $confirmation['redirect'] ) ) {
        
        // Set the root URL for the site
        $url = home_url( '/' );
        
        // Populate an array with our form entries
        $stats     = array(
            'product_category'  => rgar( $entry, '5' ), // Assign the value of input 5 to this variable
            'product_name'      => rgar( $entry, '6' ), // Assign the value of input 6 to this variable
            'variable_one'      => rgar( $entry, '7' ), // Assign the value of input 7 to this variable
            'variable_two'      => rgar( $entry, '8' ), // Assign the value of input 8 to this variable
        );
        
        // Create the redirect URL with the form inputs, and include query parameters
        $confirmation = array( 'redirect' => $url . '/' . $stats["product_category"] . '/' . $stats["product_name"] . '/?var1=' . $stats["variable_one"] . '/&var2=' . $stats["variable_two"] );
    }
    
    return $confirmation;
}