I can confirm that the filter pattern you are using is correct

I would maybe try to check if cloudtrail has been granted the required role (sometimes it might not work the first time) and provides events to the log group.

Btw. I am missing an option to upload a screenshot. Hence the link:

https://acg-root-login-1234.s3.eu-central-1.amazonaws.com/Screenshot+from+2019-06-05+14-28-27.png

Regards.