If your scope is "Does not have Ozobot Installed" the iPad falls out of scope as soon as it's finished downloading the App.
Does the device command history have a remove command for Ozobot? If so, there's something in the JSS triggering the remove command. Typically, in my experience, that's usually been scoping silliness, but there are other more unlikely possibilities. If there isn't a remove command in the history, it might be being removed during the managed app config step, though don't ask me why.
I have seen this happen when a there is an "age restriction" on that app store that is greater that the app. I had a teacher go in and add restrictions not to allow apps over 12+, the app she was installing was 17+. The app would "install" and disappear. As soon as the restriction was removed, the app appeared.
https://itunes.apple.com/us/app/ozobot/id910831867?mt=8
Ozobot is 17+, usually this is because it has some kind of built-in web browser.