It is correct that the default value does not get applied with the latest version - 2019.2.619. This is a regression introduced in the data source which indirectly affect the grid.
As a temporary solution, I can suggest that you either download the latest internal build or revert back to the 2019.2.514 version where the issue is not present.
Alternatively, you can opt for upgrading to the latest version next week, when an official release would take place.
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