Unless I made any mistakes in the settings (which I cannot rule out), there seem to be two issues with the "Drag and Drop" question type in the "Quiz (Question Set)" content:
1. It is only possible to drop the text areas, i.e. the answers, into the correct drop field, but not into the incorrect ones. This does, of course, make the quiz much easier than intended.
2. Despite this restriction, H5P still tells me the given answers are wrong when checking the results, which is contradictory and wrongly results in minus points.