I mean Tom Petty, Dire and Straitzo all didnt recognize those techniques before fighting Dio also. Straitzo uses them as a vampire yeah but thats decades after Dio.
Also all of the fodder Vampires across part 2 never come close to using or discovering them.
Dio may have just rediscovered lost techniques that seemingly no Vampire has used since the Pillar Men wiped out a lot of the Hamon tribes, but well seemingly no Hamon user knew about any of those techniques, even the most well informed ones who had faced Vampires before. In effect of the story, Dio created the method he uses and Straizto copied that.