Greetings
In order to see the Clip Monitor Set Zone Out on the timeline the Clip Monitor Set Zone Out should add 1 frame.
ATM it is Clip Monitor Set Zone Out = Clip Monitor Set Zone Out minus one on the Project Monitor.
Please open a bug report in bugs.kde.org and provide screenshots so the devs can better troubleshoot and replicate the issue. Thanks!
Oh. I never thought of it as a bug. Seems hardly worth it 
to make a case against possible difference in a frame
Well, IMO it should be frame-exact. So if Kdenlive drops one frame from the set zone it is not correct. Likewise, I am not sure whether adding one is correct either …
Since you raised it and seem to have a good clip to show it clearly, I think you should report this bug