There is a good chance the Trackpad and Trackpad IPD Flex Cable is damaged. I find that liquid damage is common since the cable connection is right below the gap at the top of the Trackpad. Plus the keyboard is connected to the Trackpad which is why the Keyboard is also not working. There is also a possibility the issue is with the Logic Board. In my own personal experiencing supporting our organization's MBAirs the Trackpad & Trackpad Flex Cable are most likely the issue. If there is liquid damage or corrosion on the cable connector, then both parts need to be replaced since it is not possible to clean the inside of the connector.
Have Apple or an Apple Authorized Service Provider examine the laptop to provide you with a repair estimate.