It says has adapted many katas to modern times-meaning it has taken old katas and applied to modern times =Goshinjutsu.The implication is clear though, since they didnāt mention where they actually got those techniques, and mention adapted kata instead of just saying they learned it from Bjj. They could have easily just said that in modern times they adapt many modern disciplines, and gave credit where credit is due.
It also says has a sub set ground curriculum of 30 techniques- Which implies additonal or part of what they teach. He does not say our ground curriculum is part of Shinden Fudo ryu as a subset nor does he say our ground curriculum is part of an ancient kata implying it is from anything ninjutsu realted.
But if it bothers you so much why not ask for clarfication from them? I am sure they would be happy to explain what they meant.
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