Found this excellent site/link which lists German WW2 AFV paints. Please note the various Ral 7028 shades. I use “Google Translate” (link below) for an English translation. Just highlight the text copy and then paste to “Google Translate.”
http://www.auradesign.eu/camo_p_wh.htm
https://translate.google.com/?sl=auto&tl=en&op=translate
I’m at this point as many, if I’m close enough with a particular RAL 7028 shade and it looks good to me, I’m good to go…