Which is the original mantis system?

Recently I was in Wai Yearn China, the ancestral home of Lau Soei. The name of the arts used there was Doong Gong (East River) Praying Mantis. There was a mention of Chow Gar Praying Mantis, that Lau Soei used the Character is Chow and is pronounced as Chu in Hakka. This is unlike the Character Chu (Royal) used in Hong Kong. Well going back to all this, it really does not matter whether it is Chu or Chow or Jook Lum. Because all these arts including the dragon sign or Pak Mei were none other than Hakka Martial arts. These names were added when they came to Hong Kong. But proof is that the 3 tigers of Wai Yearn doong gong, were in fact Lau Soei, Cheung La Chun and Lum Yu Gwai