This area seems to be in the municipality of Weismes / Waimes instead of Eupen. At least the German wikipedia states that the old Monschau train station (situated right here) is located in the municipality of Weismes / Waimes. [1,2] This seems to be based on an article of Aachener Nachrichten [3]. Does anyone know how to officially check the extent of the border of Weismes / Waimes? Or is this sufficient for changing the border?

Sources:
[1] https://de.wikipedia.org/wiki/Weismes#Lage
[2] https://de.wikipedia.org/wiki/Monschau#Verkehr
[3] http://www.aachener-nachrichten.de/mobile/lokales/eifel/kuriositaeten-im-eifeler-grenzgebiet-1.471974