The first map with the explicit ID's is shown correct in the page, but the second map with the SPARQL query is not shown at all.

Cannot reproduce. It is shown for me on https://da.wikipedia.org/w/index.php?title=Bruger:Dipsacus_fullonum/sandkasse&oldid=9957579

@Dipsacus_fullonum: If it is not shown, what is there instead? Can you take a look at the source of that HTML page?

@Aklapper: Now the second map with the SPARQL query is also correct for me. But when the page was created it was only shown as a frame with the legend, but where the map should be, there was only a white empty space.

When I press "Edit" and then "Show preview", now the preview of both maps are missing 2 of the 3 countries (Bosnia and Hercegovina, and Montrenegro). Before it was only the first map, while the second was correct in the preview.

Missing country polygons on dynamic map (page preview) seem to be be related to T218097.

While different behaviour for these two maps seem to be due to T214984. With PHP7 the second map with SPARQL query gives "Couldn't parse JSON" error and with HHVM both maps work. On da.wikipedia.org I currently get HHVM as a logged-in user and if I log out I get PHP7.

Things keep changing. At the same page (https://da.wikipedia.org/w/index.php?title=Bruger:Dipsacus_fullonum/sandkasse&oldid=9957579) now the first map, with Wikidata ID's explicit in the JSON code, only show the geoshape for Croatia.

The second map with the SPARQL query now only shows the frame, the legend, the copyright message, and the button for an interactive fullscreen button, but no map at all. When the button is pressed, I get a interactive map with only Croatia marked.