Hi there!
The closest I manage to get were Solved: Showing Zero "0" in workspace and Visits showing zero for pages but has "Entries"..., but I have a little bit different case. Here Solved: adobe campaign delivery label visits showing "0" also I found valuable thoughts.
Goal was: to analyse digital campaign - page & user behavior
Did a quick segment (hot): campaign code (dimensions expires on visit) = abc
Got page URL to the table (expire on visit)
Added users, visits, time on site - all were going good. Apparently, added Exits and here popped up suspicious pages with 0 visits, but exits. First I thought something is setting this variable somewhere else, but occurrences are 0 which for me means, that this value was not set in image request.

For something to be in the table user must perceive a tracking code, but how he can exit from something without coming there?
Imaginary scenario: he opened the page in the tab and set this tab aside, then he saw an ad, clicked on it, landed on different page, then closed his browser? So he literally obtained the tracking code after opening the page i'm interested in, had no hits with it, but exit having the tracking code and all the tabs were affected by it?