It appears that Dutch Wikipedia's edit quality campaign got loaded with the wrong revision IDs.
I've unloaded and reloaded the campaign with the right IDs. Hopefully that gets it.
FYI, you can see me make the mistake at the end of my worklog on this date: https://meta.wikimedia.org/wiki/Research_talk:Revision_scoring_as_a_service/Work_log/2015-11-12
It appears to be working. I requested a new workset and I'm seeing normal revisions, no errors.