>>1607396 lb
Well I don't think it is on their crest. The red shield was a hexagram, seen in the upper left.
But ((they)) definitely use the red cross in many places.
The red cross seems related to the Templars and the flag of England. It looks like the Templars were formed in 1119. The earliest use of the flag was 1188.
Weren't vampires supposed to be afraid of the cross? Maybe because it is red, it changes its meaning for them, as a kind of mockery of the sacred?