Yeah but was he a sandan before or after he started BJJ? If he wasn't a sandan, then he doesn't count. Then, what style is he if he was a sandan? Only two styles of Aikido matter and he's had to of trained in one for five years and the other for six months. However, the six months must of been during his third year of the first style. Of course, he had to of returned to the second after his five years of the first to pursue his sandan.