The Company is not liable for expenses you incur if you miss your flight or flight connection. In They are offering only a voucher to rebook.
You are correct that gratuities are not included in your purchase price. Passenger Ticket Contract Terms and Conditions for more information. Click on the hyperlink below to access the full Forum transcript. The complainant verified the issue was resolved to their satisfaction. Routings are not guaranteed and are subject to change at any time.