from my understanding 'capacity' is the number of cars that can charge simultaniously. So yes - 3 Stations that can charge 5 cars at the same time is correct. Maybe even 6 cars can charge, but I do not know whether the trippelcharger is able to charge 2 cars simultaniously. Some do have this features while others don't.

there are 3 separate stations. See the pictures I took at https://www.goingelectric.de/stromtankstellen/Slowakei/Bratislava/Novy-Ruzinov-Bajkalska-45A/44506/

bol som tam a isiel som kazdy cesty peso s gpsom mnohokrat.