It
looks like the tunic may have been bleached artificially or played with but hard to say. If it was proper sun fading, one thing that I would probably expect to see is some darker areas where a belt or the other medals were worn (unless it has been displayed somewhere exposed to sun for a long time without medals and the cloth DKiG and TDB was removed later). I would also think that an examination of areas such as under the pocket flaps and ares covered by the collar should reveal whether the colour differences where the DKiG was is really due to sun fading?
Without seeing more pics of these areas it is hard to say.
Just my thoughts, always learning
BC