You can absolutely use the Pik app to access the content, but the Crave apps/website should work too. I'd try logging out and logging back in on Crave - it's working for me. Remember that during the login flow, select sign in 'Through my TV Provider', then choose TELUS, then 'My TELUS'. Your credentials will be the same as what you use to log in to the Pik TV app or to telus.com/mytelus.
Using my TELUS credentials to log in to third party apps is a pretty new capability for Pik TV customers, so a log out and log back in on Crave may be required to reset.