Really? Jehovah's Witnesses were put into camps because they saw Jesus as their only king and not the fuehrer? How was that not the case of all Christians? Catholic priests were put a red triangle, political enemies.
I always thought Bible Students were put into camps because the nazis didn't agree with the Watchtower hierarchy. Also they were trustworthy, unlike any other prisioner.
Bizarre? Nazism was an ideology obssesed with symbolism, but maybe you are right and they didn't pay any attention to the colors they used.