Perhaps the model kit has provided a generic name for 'Deutsches Grau/German Gray'. Germans had a lot of grey colors - this is all in addition to the RAL Grau colors.
RLM 02 RLM Grey
RLM 63 Light Grey (lichtgrau)
RLM 66 Black-Grey (schwartzgrau)
RLM 74 Grey-Green (grungrau)
RLM 75 Grey-Violet (mittlegrau)
RLM 77 Light-Grey (hellblau)
RLM 92 Cockpit Grey
Peace,
John