I've run into the following issue:
When using authnz_ldap authentication with thruk via SSL, the comments/acks/DTs author name is set to none.
I can see in the Current Network Status bar that my username is correctly registered there. I also found the following line in the thruk log:
[2017/11/30 23:29:17][test-server.test.com][INFO][Thruk] [testuser][External Shinken] cmd: COMMAND  ADD_SVC_COMMENT;test-server;CSF status;1;none;test
Where testuser is my actual username and none is the username sent to shinken.