Version: CC19 (14.0.1) on Mac OS 10.13.6 (High Sierra)

When there are datamerge-placeholders that are not in the datasource, the export aborts and you have to delete the placeholder.
When these placeholders are on invisible layers the same happens.

In my case, sometimes i get different datasources for different versions of the same document so i put the different version on a new layer and make it invisible until i use the corresponding datasource for it.

Maybe a choice for the user to continue nontheless (only when placeholders are on invisible layers, to protect the user from using the wrong datasource on visible layers) would be a nice way of handling that situation instead of aborting immediatly. It would be more flexible and yet still warning the user about missing datasource-fields.

A second solution could be, to set a flag on the affected fields in the datamerge-panel, so they get ignored by the placeholder check. That way i could use them on my invisible layer without the need to delete them for export.