Calling the function AuthCheckFilter.addExclude("my_plugin/something/*") dose not allow access to my pages under something/*.
Fixed by setting “adminConsole.access.allow-wildcards-in-excludes” system property to “true”
Good to see that you have found the answer already! Please be aware that setting that setting has some security implications (it makes it easier for bugs to expose parts of your server that you really do not want to expose publicly). If you can find a way to fix your plugin without doing that, that would be best.