Judo is the forerunner of BJJ and while they have added techniques it is still the nucleus of their system. Boxing/wing chun and you have it. It reminds me of the Wing Chun story. Who has the correct system from Yip Man, truth is there is other interprations and all valid. I know in Germany we have people who are Turkish who added wrestling from turky to their system. They then call this for example Avci Wing Tzun. The Martial arts are always changing.