I was able to talk to a coworker and he helped figure this out. Wanted to let other's know the solution.
I found out that you can find estimated time ranges within the query.
Query 1 will give estimated times <= 5 minutes, and Query 2 will give estimated times >= 5 minutes.
Armed with this knowledge, we realized we can find empty estimated times by finding anything outside the 0 to 99 hour range.
project = MGS and issue NOT IN coveredByTestCasesHavingField("estimatedTime", "00:00" , "99:59")
This method requires that a test case is linked to an issue. There may be another way to do this, I am interested to hear if there are other solutions, or better yet if there is a way to do this within Zephyr without needing to be linked to an issue.
