Oh an update, I was only able to use the custom UI by leaving out zoomSDK.getMeetingSettingsHelper().setCustomizedMeetingUIEnabled(true); from my Activity.
When I do not include that but set zm_config_conf_activity to my custom class, it runs the custom class and I see the custom UI but in MeetingServiceImpl.class handleUriAction PTApp.getInstance().isSdkEnableCustomizedUI() && PreferenceUtil.readBooleanValue(“sdk_use_customized_meeting_ui”, false)) returns false
When I call zoomSDK.getMeetingSettingsHelper().setCustomizedMeetingUIEnabled(true) and setup the config file to point to the custom class it does nothing.