The multiplayer feature of the WordSearch DLC is currently not working due to the server being down. This issue started yesterday.
This is the same reason as why the Gray Swan Games website is down:
https://grayswangames.com
I have an open ticket with my server host. They tell me the data center is having technical problems and they don't know when it'll be back online. This is very frustrating and unprofessional. I hope it'll be back online very soon.
Singleplayer mode should work as usual.