On Steam and in the Dovetail Live Article you can see a coloured front ZZA (Zugzielanzeige = destination board) being used: (Source: Dovetail Live) While, yes the coloured front ZZA does exist for the modernised BR423: (Source DB) Almost all of them don't have colour: (Source: me) The side screens are the only coloured ones: (Source: me) (Sorry for the striped screens, but you can still clearly see everything you need to see)
I'm pretty sure I see colours on the pictures you attached, all modernised 423s have the same screent afaik. Edit: Just double-checked with some videos, it might also just be the dark background colour which makes it not-so-visible. If there actually are differences, DTG is making a up-to-date route with the not-so-wide-spread green stripe without plug livery on the ICE 3, so it's kinda reasonable to make the not-so-wide-spread new ZZA.
The complete orange one would be Frankfurt-only afaik, but I don't really mind which type DTG makes, as long as it is realistic.