The class that is extended by the WC_TP_Gateway class (defined in trust-payments-gateway-3ds2/classes/class-wc-tp-gateway.php), i.e. WC_Gateway_Cheque (found in woocommerce/includes/gateways/cheque/class-wc-gateway-cheque.php), returns an array with two parameters within the process_payment function (which is also defined in WC_TP_Gateway), one of which is called result and is set to success.
WooCommerce does not receive anything from the process_payment function defined in the WC_TP_Gateway class, therefore it has no way of knowing whether or not the transaction was successful.
