Is it possible to login to tricare websites with CAC?

I’m trying to file a claim for dental care and optometrist and an orthopedist. I’m active duty but stationed in a country where there is no military base (or tricare network providers). I’m so far in the hole with these claims it’s making me pull my hair out.

There’s a username and password option or a DS Login option. If I click DS Login, it redirects me to DMDC’s DS Login page, with options to login via CAC or username/pw. If I select CAC, I’m able to login successfully, but it doesn’t redirect me back to the Tricare page.

I called local IT, they said call DMDC, who said Tricare doesn’t accept CAC login.